How to add more information about authors with the Bibliography module?
Create another content type like "BookAuthor" with 1 node for each such Author. Then add fields to this content type for attributes such as picture, biography and nationality.

Assume you have a content type like "Ressources" (or just create one). Add a field in that content type using the Entity reference module for it (probably with multiple values allowed). That way you can add one or more "links" in each Ressources-node to relevant nodes of type BookAuthor.

PS: just to avoid possible surprises, I would not call the content type "Author" (which has a special meaning in Drupal, so better to not confuse Drupal with the same name for your extra content type).