APA (7th ed.) Citation

Hobart, H. M. (1911). The electric propulsion of ships. Harper.

Chicago Style (17th ed.) Citation

Hobart, H. M. The Electric Propulsion of Ships. London, New York: Harper, 1911.

MLA (9th ed.) Citation

Hobart, H. M. The Electric Propulsion of Ships. Harper, 1911.