United States. General Accounting Office
United States. Agricultural Research Service
Michael J. Singer
Edward J. Plaster
Roy Luther Donahue
Gruiz Katalin
Johannes Lehmann
United States. Naval Facilities Engineering Command
H. D. Foth
United States. Congress. House. Committee on Agriculture. Subcommittee on Conservation and Credit.
Gervase Markham
Peter Tompkins
Unknown Author
Grace Gershuny
Fatima M. S. Moreira
Alan Wild
Timothy J. Havranek
United States. Army. Corps of Engineers.