Cita APA (7th ed.)

rolston, H. Conserving natural value. columbia university press.

Cita Chicago (17th ed.)

rolston, Holmes. Conserving Natural Value. New York: columbia university press.

Cita MLA (9th ed.)

rolston, Holmes. Conserving Natural Value. columbia university press.

Atenció: Aquestes cites poden no estar 100% correctes.