show me airlines that have flights between toronto and detroit between detroit and st. louis and between st. louis and toronto
O O O O O O O B-fromloc.city_name O B-toloc.city_name O B-fromloc.city_name O B-toloc.city_name I-toloc.city_name O O B-fromloc.city_name I-fromloc.city_name O B-toloc.city_name