function add_role_filter_to_posts_administration(){

    //execute only on the 'post' content type
    global $post_type;
    if($post_type == 'post'){

        $user_role  = '';
        // Get all user roles
        $user_roles = array();
        foreach ( get_editable_roles() as $key => $values ) :
            $user_roles[ $key ] = $values['name'];
        endforeach;
        // Set a selected user role
        if ( ! empty( $_GET['user_role'] ) ) {
            $user_role  = sanitize_text_field( $_GET['user_role'] );
        }

        ?><select name='user_role'>
            <option value=''><?php _e( 'All Roles', 'papasemarone' ); ?></option><?php
            foreach ( $user_roles as $key => $value ) :
                ?><option <?php selected( $user_role, $key ); ?> value='<?php echo $key; ?>'><?php echo $value; ?></option><?php
            endforeach;
        ?></select><?php

    }

}
add_action('restrict_manage_posts','add_role_filter_to_posts_administration');