APA (7th ed.) Citation

Tompkins, P., & Bird, C. (1991). Secrets of the soil. Viking Arkana.

Chicago Style (17th ed.) Citation

Tompkins, Peter, and Christopher Bird. Secrets of the Soil. London: Viking Arkana, 1991.

MLA (9th ed.) Citation

Tompkins, Peter, and Christopher Bird. Secrets of the Soil. Viking Arkana, 1991.