function manage_mytype_columns( $column, $post_id ) {
global $post;
        $pp_id = get_post($post_id)->post_parent; /*The post parent id is stored also as post meta, so I could also use $pp_id = get_post_meta($post_id, 'post_parent', true) ); */
        if ( empty( $pp_id ) ) {
            echo __( 'No post parent' );}
        else {
            $pp_title = get_post($pp_id)->post_title;
                            echo $pp_title; }
}
add_action( 'manage_mytype_posts_custom_column', 'manage_mytype_columns', 10, 2 );

function manage_mytype_columns( $column, $post_id ) {
global $post;
        $pp_id = get_post($post_id)->post_parent; /*The post parent id is stored also as post meta, so I could also use $pp_id = get_post_meta($post_id, 'post_parent', true) ); */
        if ( empty( $pp_id ) ) {
            echo __( 'No post parent' );}
        else {
            $pp_title = get_post($pp_id)->post_title;
                            $pp_url = add_query_arg(array('post_type' => $post->post_type, 'post_parent' => $pp_id), 'edit.php');
                           echo '<a href="'.$pp_url.'">'.$pp_title.'</a>'; }
}
add_action( 'manage_mytype_posts_custom_column', 'manage_mytype_columns', 10, 2 );

function make_post_parent_public_qv() {
    if ( is_admin() )
        $GLOBALS['wp']->add_query_var( 'post_parent' );
}
add_action( 'init', 'make_post_parent_public_qv' );