Cita APA

Richards, B. N., & Richards, B. N. (1976). Introduction to the soil ecosystem. New York, New York: Longman.

Citación estilo Chicago

Richards, Bryant N., y Bryant N. Richards. Introduction to the Soil Ecosystem. New York, New York: Longman, 1976.

Cita MLA

Richards, Bryant N., y Bryant N. Richards. Introduction to the Soil Ecosystem. New York, New York: Longman, 1976.