Cita APA (7th ed.)
Norstog, K., & Long, R. W. (1976). Plant biology. Saunders.
Cita Chicago (17th ed.)
Norstog, Knut, i Robert W. Long. Plant Biology. Philadelphia: Saunders, 1976.
Cita MLA (9th ed.)
Norstog, Knut, i Robert W. Long. Plant Biology. Saunders, 1976.
Atenció: Aquestes cites poden no estar 100% correctes.