add class to book navigation block links I use navigation block generated by block module. Tha block is displayes on all pages that belongs to book. I would like to add custom class to all links inside navigation block. I found that the block is generated by code here>

https://api.drupal.org/api/drupal/modules!book!book.module/function/book_block_view/7

But I am unable to figure out how to alter links. Any help appreciated. Thank you.
Give a try to Block class module: Block Class allows users to add classes to any block through the block's configuration interface. By adding a very short snippet of PHP to a theme's block.tpl.php file, classes can be added to the parent &lt;div class="block ..."&gt; element of a block.