APA
Clapp C. E., . (2001). Humic Substances and Chemical Contaminants: Proceedings of a workshop and symposium cosponsored by the International Humic Substances Society; Divisions S-2, S-3, S-4, and S-11 of the Soil Science Society of America; and Division A-5 of the American Society of Agronomy, Anaheim, California, 26-27 October 1997. Madison, WI: Soil Science Society of America.
Chicago
Clapp C Edward, . 2001. Humic Substances and Chemical Contaminants: Proceedings of a workshop and symposium cosponsored by the International Humic Substances Society; Divisions S-2, S-3, S-4, and S-11 of the Soil Science Society of America; and Division A-5 of the American Society of Agronomy, Anaheim, California, 26-27 October 1997. Madison, WI: Soil Science Society of America.
Harvard
Clapp C. E., . (2001). Humic Substances and Chemical Contaminants: Proceedings of a workshop and symposium cosponsored by the International Humic Substances Society; Divisions S-2, S-3, S-4, and S-11 of the Soil Science Society of America; and Division A-5 of the American Society of Agronomy, Anaheim, California, 26-27 October 1997. Madison, WI: Soil Science Society of America.
MLA
Clapp C Edward, . Humic Substances and Chemical Contaminants: Proceedings of a workshop and symposium cosponsored by the International Humic Substances Society; Divisions S-2, S-3, S-4, and S-11 of the Soil Science Society of America; and Division A-5 of the American Society of Agronomy, Anaheim, California, 26-27 October 1997. Madison, WI: Soil Science Society of America. 2001.