Kishores

This is a WordPress plugin which helps in adding 
an option to your posts to enable display of more than one author-name on a post on WordPress.
<a href="http://opentuteplus.com/wordpress-post-contributors/" rel="nofollow ugc">Demo:</a>
TODO : Ajax filter for showing author on dashboard.
<h3>Arbitrary section</h3>

WordPress Post Contributors

Add an option to your posts to enable display of more than one author-name on a post on WordPress.

mallsop

List site contributors allows you list your site’s contributors and authors. 
Just add the shortcode [listsitecontributors] to a page on your blog. 
Optionally you can use the User Photo Plugin (https://wordpress.org/extend/plugins/user-photo/) for images, 
otherwise Avatars will be used.

WordPress Post Contributors vs List Site Contributors