WordPress: Add an author filter to the admin post list

To add an author filter on the list of articles page available in WordPress, simply add the following code to the functions.php file:
Note: I have left the comment on the conditional instruction concerning the post types, it might come in handy 😊

function restrict_manage_authors() {
/*if (isset($_GET['post_type']) && post_type_exists($_GET['post_type']) && in_array(strtolower($_GET['post_type']), array('your_custom_post_types', 'here'))) {
*/wp_dropdown_users(array(
'show_option_all'	=> 'Show all Authors',
'show_option_none'	=> false,
'name'			=> 'author',
'selected'		=> !empty($_GET['author']) ? $_GET['author'] : 0,
'include_selected'	=> false
));
/*}*/
}
add_action('restrict_manage_posts', 'restrict_manage_authors');