THE COLUMBIAVIKING & BRIDGWATER, W. (1960). The columbiaviking desk encyclopedia a-k vol.1.-- Ed. 2. The Viking Press.

THE COLUMBIAVIKING and William BRIDGWATER. The Columbiaviking Desk Encyclopedia A-k Vol.1.-- Ed. 2. New York: The Viking Press, 1960.

THE COLUMBIAVIKING and William BRIDGWATER. The Columbiaviking Desk Encyclopedia A-k Vol.1.-- Ed. 2. The Viking Press, 1960.