United States. Congress. Senate. Committee on Patents
United States. National Transportation Safety Board.
Kokuritsu Kokkai Toshokan (Japan)
David J. Price
Unknown Author
New York State Academy of Fire Science. Library.
Lumbermen's Association of Chicago.
Robert Barron
United States. Congress. House. Committee on Science and Technology.
United States Grain Corporation.
United States. General Accounting Office
United States. Congress. Senate. Committee on Agriculture and Forestry
United States
Japan.
Norman Maclean
Robert N. Munsch