APA (7th ed.) Citation

Weir, W. W., & Gregory, R. W. (1946). Productive soils. J.B. Lippincott company.

Chicago Style (17th ed.) Citation

Weir, Wilbert Walter, and R. W. Gregory. Productive Soils. Chicago, Philadelphia [etc.]: J.B. Lippincott company, 1946.

MLA (9th ed.) Citation

Weir, Wilbert Walter, and R. W. Gregory. Productive Soils. J.B. Lippincott company, 1946.