First and second editions were published for the country elevator section of the Grain Trade only. The general edition was completely revised in 1939 to serve all sections of the Canadian Grain Trade. The 1939 and 1948 General editions cannot be used with any previous edition of the DRP Grain Code
"Planned and conducted by a subcommittee of the Agricultural Committee of the Greater Des Moines Chamber of Commerce."
"Published under the auspices of the Agricultural Committee of the Greater Des Moines Chamber of Commerce with the cooperation of the Iowa State University Center for Agricultural and Economic Development."