diff --git a/doc/faq/howto_faq.rst b/doc/faq/howto_faq.rst
index 22a6f7614295..c354b91b01ae 100644
--- a/doc/faq/howto_faq.rst
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@@ -481,7 +481,7 @@ though we have made significant progress towards supporting blocking events.
 .. _howto-boxplot_violinplot:
 
 Interpreting box plots and violin plots
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+---------------------------------------
 
 Tukey's `box plots <http://matplotlib.org/examples/pylab_examples/boxplot_demo.html>`_ (Robert McGill, John W. Tukey and Wayne A. Larsen: "The American Statistician" Vol. 32, No. 1, Feb., 1978, pp. 12-16) are statistical plots that provide useful information about the data distribution such as skewness. However, bar plots with error bars are still the common standard in most scientific literature, and thus, the interpretation of box plots can be challenging for the unfamiliar reader. The figure below illustrates the different visual features of a box plot.