Marshall, A. J., & Williams, W. D. (1972). Textbook of Zoology: Invertebrates (7th ed.). Macmillan.
Cita Chicago (17th ed.)Marshall, A. J., i W. D. Williams. Textbook of Zoology: Invertebrates. 7th ed. London: Macmillan, 1972.
Cita MLA (9th ed.)Marshall, A. J., i W. D. Williams. Textbook of Zoology: Invertebrates. 7th ed. Macmillan, 1972.
Atenció: Aquestes cites poden no estar 100% correctes.