an Entity references as follows:
The Martin B-57 Canberra was first manufactured in 1953, and the United States Air Force had accepted a total of 403 B-57s before production ended in early 1957. The last USAF B-57 was retired in 1983. It was the last tactical bomber used by the United States Air Force, being engaged in combat operations during the Vietnam War (1963–1971). It also performed a wide variety of other missions. This list is of the units it was assigned to, missions performed, and the bases it was stationed.