APA (7th ed.) Citation

(1990). Humic substances in soil and crop sciences: Selected readings ; proceedings of a symposium cosponsored by the International Humic Substances Society ..., Chicago, Illinois, 2 December 1985.

Chicago Style (17th ed.) Citation

Humic Substances in Soil and Crop Sciences: Selected Readings ; Proceedings of a Symposium Cosponsored by the International Humic Substances Society ..., Chicago, Illinois, 2 December 1985. Madison, Wis, 1990.

MLA (9th ed.) Citation

Humic Substances in Soil and Crop Sciences: Selected Readings ; Proceedings of a Symposium Cosponsored by the International Humic Substances Society ..., Chicago, Illinois, 2 December 1985. 1990.