APA (7th ed.) Citation

Great Britain. Central Office of Information. Reference Division. (1974). Ports. H.M.S.O..

Chicago Style (17th ed.) Citation

Great Britain. Central Office of Information. Reference Division. Ports. London: H.M.S.O., 1974.

MLA (8th ed.) Citation

Great Britain. Central Office of Information. Reference Division. Ports. H.M.S.O., 1974.