sentences:  The shorter routes were operated by Douglas DC-3s and the longer routes by Douglas DC-4s.By 1956, Colonial's executive offices were on Park Avenue in New York City and it was flying several routes including five daily nonstop DC-4 flights between LGA and Montreal.It also operated a nonstop DC-4 flight departing LGA at 11 am EST to Bermuda, arriving at Kindley Field 3