Custom posto con custom field
// WP_Query arguments $args = array( 'post_type' => array( 'pippo' ), 'author' => '123', 'meta_query' => array( array( 'key' => 'ufficioweb_id', 'value' => '356', 'compare' => '=', 'type' => 'CHAR', ), ), ); // The Query $query = new WP_Query( $args );