The british airborne forces from 1940 to 1945.

Official website of the 517th Parachute Regimental Combat Team association.

A living history of The Parachute Regiment and Airborne Forces | ParaData

The VI Corps Combat Engineers small units history.

Official - 509th Parachute Infantry Association 

Official - 551st Parachute Infantry Association

Official Home of the 463rd Parachute Field Artillery

US Naval History and Heritage Command