There are only 2 discovery mechanisms, not three

dunglas · web-flow · commit d29faa4a179d · 2018-08-28T22:14:08.000+02:00
diff --git a/source.html b/source.html
@@ -308,7 +308,7 @@ <h2>Discovery</h2>
 &lt;/html&gt;
     </pre>
 
-    <p>When perfoming discovery, subscribers MUST implement all three discovery mechanisms in the following order, stopping at the first match:</p>
+    <p>When perfoming discovery, subscribers MUST implement all two discovery mechanisms in the following order, stopping at the first match:</p>
     <ol>
       <li>Issue a GET or HEAD request to retrieve the topic URL. Subscribers MUST check for HTTP Link headers first.</li>
       <li>In the absence of HTTP Link headers, and if the topic is an XML based feed or an HTML page, subscribers MUST check for embedded link elements.</li>
