DE102010036037A1 - Method for performing cashless payment transaction in transaction system, involves examining transaction equipment identity and identifier symbol of respective mobile and merchant stations in request signal outputted to central unit - Google Patents

Abstract

A request signal (S3) comprising transaction equipment identity of mobile station (4) and transaction identifier symbol of merchant station (3), is outputted from mobile station to central unit (2). The information in request signal is examined to determine whether to perform payment transaction or not. The transaction signal comprising transaction number is sent to mobile station, when payment transaction is to be performed. A transaction confirmation signal (S6) is outputted to merchant station, when acknowledgement signal (S5) from mobile station is received. An independent claim is included for transaction system.

Description

The invention relates to a method for carrying out cashless payment transactions and to a corresponding transaction system in which this method is applicable.

State of the art

Cashless payment transactions allow buyers to avoid carrying large sums of money. This also gives the trader an advantage as he does not have to manage larger amounts of cash. Cashless payment transactions are also advantageous for operating vending machines, since the vending machines no longer have to be emptied and the customer no longer has to hold a suitable small change ready.

For this purpose, different cashless payment systems are known, for. For example, debit cards and credit cards in which the cardholder can make a cashless payment with a card associated with him and his signature, or by entering a PIN associated with that card. However, the risk of misuse is relatively high, especially if the card is lost. Furthermore, the transaction fees incurred in connection with such transactions are generally relatively high.

Furthermore, cash cards have been developed with integrated processor memory unit, in which an encryption technology is used in which amounts of money on the card can only be well written by authorized providers. Also, such payment systems are coupled to the respective card, furthermore, they require a correspondingly dense network of associated charging stations, where the cash cards can be charged by the respective institutions. Also, the merchants must provide appropriate cash card reading stations.

Furthermore, cashless payments by means of a mobile terminal, z. B. mobile terminal or smartphones have been proposed. As mobile phones have become widely used, the availability is very high and generally available to most customers at all times if they carry appropriate mobile devices with them.

The DE 199 03 822 C2 describes a method for making cashless payments by means of a merchant station, a mobile phone and a matching device comprising a dealer checker and a subscriber checker.

In the DE 103 10 508 A1 A method for the cashless payment of goods or services using a mobile terminal is presented. The payment transaction takes place via a central processing unit.

The DE 101 56 177 A1 describes a method and an arrangement for carrying out a cashless payment transaction. Here, a merchant station, a mobile terminal and a central station are used, which is connected via a data network with the mobile terminal and the merchant station.

The DE 101 53 660 A1 describes a system for processing cashless payment services, wherein the settlement takes place through the intermediary of a provider operated by a mobile communication network using mobile devices and a set up by the provider and maintained by the customer credit account.

In the EP 1 530 177 B1 and the DE 100 07 518 A1 there are shown methods of supporting cashless payments using, inter alia, a mobile communication system and an authentication server that interacts, in part, with subscriber identification modules of the mobile terminals to release access to the mobile communication system.

Such systems already allow payment transactions by means of dealer stations and mobile devices of a customer. However, such processes are sometimes very complex or not sufficiently tamper-proof due to their individual steps. These procedures are either too time-consuming or they do not adequately reflect the mutual need for trust or sufficient assurance that the respective partner is authorized in the payment transaction and that the payment actually takes place.

The invention has for its object to provide a method for performing cashless payment transactions and a corresponding transaction system with which payment transactions with high security and relatively little effort are feasible.

Disclosure of the invention

This object is achieved by a method according to claim 1 and a transaction system according to claim 13. The subclaims preferably describe further developments.

According to the invention, it is thus provided that the merchant station generates a two-dimensional, graphic transaction identifier symbol for carrying out or initiating the payment transaction. This transaction In particular, the identifier symbol can be designed as a rectangular or square area of differently colored boxes and represent a 2D bar code, ie a bar code formed in two dimensions. The two-dimensional, graphical transaction identifier icon can thus z. Example, a QR code or a PDF 417 code or a data matrix, z. B. in the formation of the transaction identifier icon.

The transaction identifier icon may be printed out by the merchant station, e.g. B. on a ticket, or even on an image output unit or display unit are displayed. It contains in this case the data relevant for the payment transaction, such as the payment amount, and a unique merchant station identifier, which is stored in the merchant station and enables unambiguous identification in the transaction system.

The customer can subsequently read in to carry out the transaction with his camera integrated in the mobile terminal this two-dimensional transaction identifier icon.

This is based on the idea that modern mobile devices generally already have an additional camera. Thus, according to the invention, the cameras already provided in mobile devices and connected to the control device of the mobile device can also be used to carry out the cashless payment transactions. In this case, it is in particular recognized that a graphic transaction identifier symbol, for. B. two-dimensional barcode, can be read very well from such a camera. In the mobile radio terminal, a recognition or interpretation of this graphic transaction identifier symbol can subsequently be carried out. In this case, it is recognized according to the invention that in general small misalignments of the graphic transaction identifier symbol with respect to the optical axis of the camera are not significant since, as with linear barcodes, the relative sequence of the symbols, e.g. As a box, is generally clearly detected.

The process of capturing the graphical transaction ID symbol or 2D barcode by the camera is associated with little effort for the customer; he only has to align the camera with this icon and activate it by pressing the appropriate button to capture the image subsequently transmitted by the mobile terminal, i. H. the mobile phone ordering station can be evaluated automatically.

The serving as a mobile phone ordering station mobile terminal thus sends a request signal to the central device, d. H. the trust payment center TPC, wherein the request signal contains the data contained in the transaction identifier symbol for the payment transaction, in particular also data on the merchant station identifier of the merchant station, and also an identifier of the mobile ordering station.

In principle, the identification number IMEI and, advantageously, the PIN which is already used in the mobile radio network can be used as identifier of the mobile radio ordering station. However, according to a preferred embodiment, additional identifiers are used for authentication in the transaction system. Thus, in addition to the required for the mobile network PIN and the IMEI corresponding transaction identifiers for the payment transaction are stored in the mobile terminal, d. H. a device-specific transactional device identifier (identification number) IK (corresponding to the IMEI) that is unique in the transaction system, and a personal identification number T-PIN (corresponding to the PIN) that is initially to be entered by the user for activating the payment system.

This z. B. be provided that the activation of the T-PIN has to be done in a certain time window before sending the request signal, so that the customer has to log in each case for payments currently and in case of loss of his mobile device for this reason, no payment transactions more feasible are.

The central unit can thus check the identifiers and authentications. Furthermore, it can check the creditworthiness of the mobile user acting as a customer based on stored data. This is done fully automatically or without the requirement that a human person has to carry out the verification. Advantageously, in or at the central unit or the TPC corresponding data on the users of the mobile phone ordering stations and the dealer are stored. The credit rating can be z. B. be stored as a flag or corresponding entry, so that a fully automatic query is enabled to subsequently release the request, or a corresponding error or notification signal to the impossibility of performing the payment transaction to the mobile device back to give.

If the check is positive, the central unit then returns an acknowledgment signal, which in particular contains a TAN signal with a transaction number (TAN) for this transaction. Furthermore, user-specific information about the mobile radio ordering station are included in the signal, the z. B. image information, in particular a photo of the user, and a dealer station identifier of the dealer station, said dealer station identifier is advantageously certified by the central facility; she can z. B. be formed by a certified logo of the dealer station and / or include a photograph of the dealer to indicate to the user or customer that the dealer had properly authenticated on the contained in the 2D bacore dealer station identifier.

These data transmitted by the central unit to the mobile radio device or the mobile radio ordering station can the user on the display device, d. H. the display of his mobile device or mobile order station are displayed, so that the customer below the payment by an appropriate input, eg. B. via the keyboard, can confirm, whereupon a corresponding actuation signal is sent via the mobile network to the TPC.

Subsequently, the TPC may send a corresponding transaction acknowledgment to the merchant station. Depending on the function of the TPC, however, this can also cache the data beforehand, and a corresponding debit to an account-providing device, or a z. B. make a credit institution of the user or mobile device owner. If the TPC as z. B. credit institution occurs, it can make the booking without prior consultation or data communication with a credit-leading institution, and later make a possible deduction from an account of the user.

The confirmation is then displayed at the dealer station to the dealer, or it is when paying at a machine z. B. directly printed a ticket or displayed the transaction at an Internet shop on the monitor of the customer.

Furthermore, a sale via a TV channel is possible, in which case the output device is not part of the dealer station, but the graphic transaction identifier icon is displayed on the television of the customer, thus serving as output device and corresponding signals via a TV Receive channel from the dealer station.

The method according to the invention and the transaction system according to the invention thus provide several advantages:
It can be used on various locations, including vending machines, Internet shops, taxis and mobile retailers. There is a very high security against counterfeiting. The dealer can display the photo of the customer on the display device of the mobile device (mobile phone ordering station). Conversely, the customer sees the certified logo and / or a photograph of the dealer. Furthermore, both parties are already ensured by the data link to the TPC and the identifiers used both the mobile phone ordering station and the dealer station high security. Thus, by the involvement of a TPC a payment can be carried out, get in the security-related data of the buyer, such as his identifier, not in the knowledge of the dealer. Thus, according to the invention, a secure and anonymous payment by the customer is made possible without his relevant secret data being disclosed and subsequently used for fake actions.

The method according to the invention and the transaction system occur without much hardware effort. In principle, only mobile radio ordering stations are required, which can be used directly as mobile devices. The upgrade of a conventional mobile device to a mobile ordering station can, for. B. only by the additional software, d. H. an application for the mobile device can be achieved if the mobile device - in the usual way - already has a display or a camera.

In particular, the method according to the invention is also independent of the type of mobile radio contract. Thus, different mobile networks can be used by the different users or mobile ordering stations; Ultimately, only the data connection from the mobile device to the TPC via a mobile radio network or several mobile radio networks is relevant. Thus, users of a pay back account can pay cashless at the dealer.

According to the invention, the payment transactions can also be used for transactions in an Internet shop, for paper-based bills, for person-to-person transfers and also for purchases with offers via a TV channel. This ensures high variability and flexibility.

Description of preferred embodiments

The invention will be explained in more detail below with reference to the accompanying drawings in some forms of expression. Show it:

1 a block diagram of a transaction system according to the invention according to an embodiment of the invention;

2 Supervision of two-dimensional barcodes for use in the transaction systems of 1 ;

3 a flowchart of the inventive method according to this embodiment.

An in 1 shown transaction system 1 For cashless payment transactions, the central unit is a Trusted Payment Center TPC 2 and a variety of dealer stations 3 as well as a variety of mobile cellular ordering stations 4 on, of which in 1 a dealer station 3 and a mobile order station 4 shown in more detail. The TPC 2 is in data communication with a financial institution 5 , z. B. a bank.

It can basically be between any mobile phone ordering station 4 and every dealer station 3 Financial transactions are carried out. The mobile ordering stations 4 are conventional mobile terminals with suitable software and one or more mobile networks 7 , which are indicated here as a dashed block, with the central unit 2 connected. The dealer stations 3 can in different ways or via different media with the central unit 2 be connected, z. Via an internet 6 , The dealer stations 3 can be stationary or mobile.

The dealer stations 3 each have a computing device 3-1 , a display device 3-2 and an internet interface 3-8 on. Instead of the display device 3-2 can z. B. also be provided a printer output device. Furthermore, in a memory 3-3 stored a unique dealer station identifier HK.

The mobile ordering stations 4 each have an air interface 4-1 , z. As a GSM interface, for communication via the mobile network 7 with an air interface 2-1 of the TPC 2 on, continue a control device 4-2 , one or more data stores 4-3 and a camera 4-4 auf, in the usual way image signals S1 to the controller 4-2 outputs. In the one or more (symbolized) data stores are 4-3 on the one hand, an IMEI as a device-specific unambiguous identifier in the mobile radio network and a PIN to be entered for the registration (eg on an inserted SIM card), as well as a device-specific, unique transaction device identifier IK in the transaction system 1 and one to log in to the transaction system 1 T-PIN to be entered. The unique transaction device identifier IK can advantageously not be changed by the user, it thus corresponds to the IMEI, but is advantageously different from this.

The following is an example of initiating and executing a financial transaction.

A customer using a mobile phone ordering station 4 agrees with a dealer who has a dealer station 3 has to pay for an item or service.

In order to carry out the financial transaction, the dealer first of all gives the amount to be paid, if appropriate also data about the sold article or the sold service, if necessary additionally a designation of the reason of the financial transaction in his computing device 3-1 , Below is the computing device 3-1 according to 2 in a step St0 a TAN request signal S10 in which its dealer station identifier HK is indicated, and transmits the TAN request signal S10 via the Internet 6 to the TPC 2 to request a transaction number TAN for the transaction to be completed. The TPC 2 performs a check of the dealer station identifier HK and responds after a positive check in step St1 with a TAN command signal S11.

Subsequently, the computing device takes 3-1 the stored data of the dealer station identifier HK from the memory 3-3 and the data entered by the user about the financial transaction and outputs an output signal S2 to the display device 3-2 which then generates a two-dimensional graphical transaction identifier icon according to step St2 10 indicates that z. B. may be a 2D barcode. Examples of such a two-dimensional graphical transaction identifier icon 10 are in 2 shown, it will be in the following z. T. exemplarily referred to as a 2D barcode. The graphic transaction identifier icon 10 thus contains data on the financial amount, if necessary, the reason for payment, as well as continue the unique dealer station identifier HK the dealer station 3 ,

The graphic transaction identifier icon 10 advantageously has special security features, in particular can be protected by a password. He can in particular according to 2a) as a QR code, 2 B) as PDF 417 (Portable Data File) or 2c) be designed as a data matrix. With a code PDF 417 - depending on the output quality and the degree of error correction - a pitch of up to 100 bits / cm ² (binary) can be achieved, with a data matrix even higher pitches can be achieved. The graphic transaction identifier icon 10 is z. B. from small matrix elements 10-1 or boxes, squares or other planar elements of different color values, e.g. As white and black, composed.

The customer authorizes himself at his mobile radio ordering station in a step St3 4 via an identification number T-PIN to be entered. This authorization is thus advantageously carried out separately from the authorization when logging into the mobile network 7 with the T-PIN; Thus, the customer is generally initially by a designated PIN in the mobile network 7 log in and subsequently use the T-PIN to make payment transactions to the controller 4-2 authorize.

Subsequently, in step St4, the displayed 2D barcode 10 from the integrated camera 4-4 the mobile order station 4 recorded and read. The camera 4-4 outputs a corresponding image signal S1 to the control device 4-2 that advantageously performs image recognition and that in the 2D barcode 10 takes coded information.

Subsequently, in step St5, the mobile ordering station 4 a request signal S3 via the mobile network 7 to the TPC 2 , The request signal S3 thus contains data of the recorded and evaluated 2D barcode 10 in the store 4-3 stored T-PIN, and advantageously the unique transaction identification number IK.

In step St6, subsequent is done in the TPC 2 a check of the data transmitted with the request signal S3, this check in particular an examination of the authenticity of the user, ie his mobile phone ordering station 4 , As well as advantageously also the examination of the credit rating that this user or his mobile order station 4 is released; this can be indicated by a credit flag B. is set to "missing credit" in the absence of creditworthiness of the user accordingly. Furthermore, the TPC checks 2 the authenticity of the dealer, ie his dealer station 3 , from the over the 2D-Bacorde 10 outputted data which has been transmitted in accordance with the request signal S3. If necessary, this can be done in the TPC 2 a match with the previous request in the station 3 for the TAN.

After the exam in the TPC 2 has proceeded positively by the corresponding data adjustment, in step St7 the unique transaction number TAN as signal S4 to the mobile radio ordering station 4 over the mobile network 7 transfer. In the case of a negative test result, a cancellation signal or error signal, if appropriate with indication of the error reason, is sent to the mobile radio ordering station accordingly 4 , preferably also to the dealer station 3 , transfer.

Upon receipt of the TAN signal S4, the controller forms 4-2 the mobile order station 4 subsequently in step St8 display signals for display on the display device 4-5 , whereby the financial amount to be paid, z. For example, the user's photo, the certified logo, the dealer's station 3 and the unique transaction number TAN. The photo of the user can z. B. in memory 4-3 or another memory stored.

The user operates in step St9 z. B. an input key of the input device 4-6 , z. B. the Enter button or OK button, his mobile phone ordering station 4 , (or he enters a speech signal in speech recognition, so that the microphone is the input device), whereupon in step St10 this confirmation as confirmation signal S5 via the mobile network 7 to the TPC 2 is transmitted.

The TPC 2 receives the confirmation signal S5 and, in step St11, issues a transaction confirmation signal S6 via the Internet 6 to the dealer station 3 out, where they the dealer on z. B. the display device 3-2 or another display device is displayed.

Thus, the financial transaction is completed.

As the output device instead of the display device 3-2 an issue on a paper voucher or other area ticket done, continue even when paying on the Internet, ie training the dealer station 3 as an internet shop, graphically displayed on an internet site. According to another embodiment, the 2D Bacorde 10 on a display (display) of vending machines, z. As for tickets, confectionery, cigarettes, etc., are presented.

Furthermore, z. Example, the representation of the 2D Bacordes 10 possible on a TV of the customer. In such an embodiment, thus, the display device 3-2 not part of the dealer station 3 but the computing device 3-1 outputs the output signal S2 as a television signal to the external display device 3-2 customer serving TV.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19903822 C2 [0006]
• DE 10310508 A1 [0007]
• DE 10156177 A1 [0008]
• DE 10153660 A1 [0009]
• EP 1530177 B1 [0010]
• DE 10007518 A1 [0010]

Claims (13)

Method for carrying out a cashless payment transaction in a transaction system ( 1 ), which has a central facility ( 2 ), a multitude of dealer stations ( 3 ) and a variety of portable mobile order stations ( 4 ), wherein each mobile radio ordering station ( 4 ) an air interface ( 4-1 ) for communication with the central station ( 2 ) via a mobile network ( 7 ), a control device ( 4-2 ), a display device ( 4-5 ) and a unique mobile network device identifier (IMEI) for the mobile network ( 7 ), and wherein each dealer station ( 3 ) a unique dealer station identifier (HK) and a computing device ( 3-1 ) and with the central station ( 2 ) via a data connection ( 6 ) is in data communication, characterized in that each mobile radio ordering station ( 4 ) a transaction device identifier (IK) for unique identification in the transaction system ( 1 ) and a camera ( 4-4 ) for capturing an image and outputting an image signal (S1) to the control device ( 4-2 ), and by the computing device ( 3-1 ) of each dealer station ( 3 ) an output device ( 3-2 ) is controllable for outputting a two-dimensional graphic transaction identifier symbol ( 10 ) containing the unique merchant station identifier (HK) and transaction data, the method comprising at least the following steps: - controlling the dispenser ( 3-2 ) by the computing device ( 3-1 ) of the dealer station ( 3 ) for issuing the two-dimensional transaction identifier symbol ( 10 ) by the output device ( 3-2 ) (St2) - capture the two-dimensional transaction identifier symbol ( 10 ) through the camera ( 4-4 ) and output of an image signal (S1) to the control device ( 4-2 ) of the mobile radio ordering station ( 4 ) (St4), output of a request signal (S3) by the mobile radio ordering station ( 4 ) over the mobile network ( 7 ) to the central unit ( 2 ), wherein the request signal (S3) at least the unique transaction device identifier (IK) of the mobile radio ordering station ( 4 ) and from the two-dimensional transaction identifier ( 10 ) extracted information about the unique dealer station identifier (HK) and the transaction data contains (St5), - receiving the request signal (S3) by the central device ( 2 ) and checking or evaluating the authenticity of at least the contained transaction device identifier (IK) and the merchant station identifier (HK), and depending on the check or rating, enabling or disabling the transaction (St6), - in case of release of the transaction issue a TAN signal (S4) from the central device ( 2 ) to the mobile radio ordering station ( 4 ), the TAN signal ( 4 ) contains a unique transaction number (TAN) (St7), - displaying an image signal on the display device ( 4-5 ) of the mobile radio ordering station ( 4 ), wherein the image signal contains at least information about the transaction and about the dealer station ( 3 ) as well as the transaction number (TAN) (St8), - in the case of the entry of a confirmation signal into the mobile radio ordering station ( 4 ) via an input device ( 4-6 ) of the mobile radio ordering station ( 4 ) (St9) transmission of the acknowledgment signal (S5) over the cellular network ( 7 ) to the central facility ( 2 ) (St10), and - issuing a transaction confirmation signal (S6) from the central facility ( 2 ) to the dealer station ( 3 ) (St11). Method according to Claim 1, characterized in that the mobile radio ordering station ( 4 ) before at least the step (St5) of the output of the request signal (S3) is to be released by entering (St3) a transaction user identifier (T-PIN). Method according to Claim 2, characterized in that the transaction user identification (T-PIN) is different from a mobile user ID (PIN) required for registration in the mobile network, and the transaction device identifier (IK) is different from the mobile network device identifier (IMEI). is different. Method according to one of the preceding claims, characterized in that the unique transaction number (TAN) already before the step (St2) of the output of the two-dimensional transaction identifier symbol (TAN) ( 10 ) is generated in at least the following steps: output of a TAN request signal (S10) from the dealer station ( 3 ) to which the central unit ( 2 ), wherein the TAN request signal (S10) contains the dealer station identifier (HK) (St0), and - evaluation of the TAN request signal by the central unit ( 2 ) and, if the evaluation is positive, answering by a TAN command signal (S11) to the dealer station ( 3 ) (St1). Method according to one of the preceding claims, characterized in that in an internal or external memory of the central unit ( 2 ) Rating flags, e.g. B. creditworthiness flags for rating the creditworthiness of at least the mobile radio ordering station ( 4 ), and in the step (St6) of checking or evaluating the request signal (S3), a check or evaluation of the evaluation flag is additionally performed, and the release is made depending on this evaluation. Method according to one of the preceding claims, characterized in that the output device ( 3-2 ) a display device ( 3-2 ) of the Dealer station ( 3 ) is, for. A monitor or display, and the two-dimensional transaction identifier icon ( 10 ) graphically on the display device ( 3-2 ) and the camera ( 4-4 ) of the mobile radio ordering station ( 4 ) on the display device ( 3-2 ) illustrated two-dimensional transaction identifier symbol ( 10 ) detected. Method according to one of claims 1 to 5, characterized in that the output device is a printer of the dealer station ( 3 ) that contains the graphical transaction ID icon ( 10 ) on a solid medium, e.g. Paper, for subsequent capture by the camera ( 4-4 ) of the mobile radio ordering station ( 4 ). Method according to one of claims 1 to 5, characterized in that the output device is one of the dealer station ( 3 ) is separate, external display device, which is, for. B. a TV receiver, wherein the graphic transaction identifier icon ( 10 ) is transmitted via a remote data transmission, in particular a television channel, to the external display device. Method according to one of the preceding claims, characterized in that the two-dimensional transaction identifier symbol ( 10 ) is encoded and / or encrypted, preferably by means of an identifier or a password, for. By means of an asymmetric encryption protocol. Method according to one of the preceding claims, characterized in that the graphical two-dimensional transaction identifier symbol ( 10 ) a 2D barcode and / or a two-dimensional array of area units, e.g. As squares, is, for. For example, a QR code or a PDF 417 code or a data matrix. Method according to one of the preceding claims, characterized in that the central unit is a trust payment center ( 2 ) for the execution and approval of payment transactions concluded with a financial institution ( 5 ) is in data communication. Method according to one of the preceding claims, characterized in that, in step (St8), the display of the image signal on the display device ( 4-5 ) the displayed image signal the transaction number (TAN) and / or user-specific information via the mobile station ( 4 ) and / or certified data, e.g. B. a logo, the dealer station ( 3 ) contains. Transaction system ( 1 ) for carrying out a method according to one of the preceding claims, wherein the transaction system ( 1 ) at least comprising: a central processing unit ( 2 ), a multitude of dealer stations ( 3 ), each comprising: - a computing device ( 3-1 ), - an interface ( 3-8 ) for data communication with the central unit ( 2 ) and - at least one memory ( 3-3 ) for a dealer station identifier (HK), wherein the computing device ( 3-1 ) an indication signal (S2) to a display device ( 3-2 ) is output to display a two-dimensional graphical transaction identifier symbol ( 10 ), and a large number of mobile radio ordering stations ( 4 ), each comprising: - an air interface ( 4-1 ) for data communication over a mobile radio network ( 7 ), whereby via the mobile network ( 7 ) also the central unit ( 2 ) is bi-directionally contactable, - a control device ( 4-2 ), - an input device ( 4-6 ), - a display device ( 4-5 ), - a camera ( 4-4 ), and - a memory ( 4-3 ) for a personal identification number (PIN) within the transaction system ( 1 ).

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