Cita APA (7th ed.)
Havis, J. R. (1950). Herbicidal Properties of petroleum hydrocarbons.
Cita Chicago (17th ed.)
Havis, John R. Herbicidal Properties of Petroleum Hydrocarbons. Ithaca, 1950.
Cita MLA (9th ed.)
Havis, John R. Herbicidal Properties of Petroleum Hydrocarbons. 1950.
Atenció: Aquestes cites poden no estar 100% correctes.