ISBN 1-84037-130-7*Vector site development of Sunderland through Empire boats==External links==* British Aircraft of WW2* Century of Flight entry**ATLANTIC ROUTINE "Flight" 1937 - contemporary article on Sikorksy S42 and Empire "Caledonia" operating across Atlantic* [http://images.google.com/hosted/life/a81e23604ed0d544.html] LIFE photos by Margaret Bourke-White of CAVALIER and its competitor the Bermuda Clipper New York area 1937* [http://images.google.com/hosted/life/94b0fc16af17afd5.html] LIFE photos by Margaret Bourke-White of CALEDONIA with a Beech Staggerwing near Central Park New York City July 1937* [http://images.google.com/hosted/life/64c028a70b50b424.html] LIFE colour photos by Dmitri Kessel of CLARE at the La Guardia Marine Terminal New York City, during a series of mail/courier flights it, and CLYDE, operated to New York via Newfoundland during the Battle of Britain, 1940
Airlife Publishing, 2000.