I'm wanting to create a list of categories for a custom post type in Wordpress.
The custom post type is 'Books' and this has been set-up using the standard
taxonomies' => array( 'category', 'post_tag' ),
I'm not sure if there is a way to make
<?php wp_list_categories(); ?> just show catgories from the post-type books.
I don't want to have to create a custom taxonomy as well.