diff --git a/doc/filters/html_to_markdown.rst b/doc/filters/html_to_markdown.rst
index d382724e4..66706e92d 100644
--- a/doc/filters/html_to_markdown.rst
+++ b/doc/filters/html_to_markdown.rst
@@ -61,9 +61,9 @@ You can also use the filter on an entire template which you ``include``:
 ``html_to_markdown`` is just a frontend; the actual conversion is done by one of
 the following compatible libraries, from which you can choose:
 
-* [erusev/parsedown](https://github.com/erusev/parsedown)
-* [thephpleague/html-to-markdown](https://github.com/thephpleague/html-to-markdown)
-* [michelf/php-markdown](https://github.com/michelf/php-markdown)
+* `erusev/parsedown`_
+* `league/html-to-markdown`_
+* `michelf/php-markdown`_
 
 Depending on the library, you can also add some options by passing them as an argument
 to the filter. Example for ``league/html-to-markdown``:
@@ -76,3 +76,6 @@ to the filter. Example for ``league/html-to-markdown``:
         </html>
     {% endapply %}
     
+.. _erusev/parsedown: https://github.com/erusev/parsedown
+.. _league/html-to-markdown: https://github.com/thephpleague/html-to-markdown
+.. _michelf/php-markdown: https://github.com/michelf/php-markdown