1. Al Wrigley, “Judging the Material Winners,” American Metal Market (March 29,1993).
2. Metal working News (February 26, 1990), p. 4.
3. Rober W. Roig et al., “Impacts of Material Substitution in Automobile Manufacture on Resource Recovery,” EPA-600/5-76-007a (July 1976), PB 257 542, U.S. Environmental Protection Agency, Washington, D.C.
4. Itaru Niimi, “The Japanese Picture,” The Impacts of Material Substitution on the Recyclability of Automobiles (New York: American Society of Mechanical Engineers, 1983).
5. Howard Ness, “The Automobile Scrap Processing Industry,” The Impacts of Material Substitution on the Recyclability of Automobiles (New York: American Society of Mechanical Engineers, 1984), pp. 39–98.