A New Standardized Method for Measuring Humic and Fulvic Acid Concentrations in Commercial Products.
Richard T. Lamar, Horizon Ag, Louisville, CO, Daniel C. Olk, 1015 N. University Blvd., USDA-ARS National Laboratory for Agriculture and the Environment, Ames, IA, US, Lawrence Mayhew, Eco Agri-Minerals, Spring Green, WI and Paul R. Bloom, 1991 Upper Buford Cir., University of Minnesota-Twin Cities, St. Paul, MN