APA (7th ed.) Citation

Stewart, J. D. Gibraltar: The keystone / John D. Stewart. London : John Murray, cop. 1967.

Chicago Style (17th ed.) Citation

Stewart, John David. Gibraltar: The Keystone / John D. Stewart. London : John Murray, cop. 1967.

MLA (8th ed.) Citation

Stewart, John David. Gibraltar: The Keystone / John D. Stewart. London : John Murray, cop. 1967.

Warning: These citations may not always be 100% accurate.