1. ?Municipal Solid Waste Disposal in the 1990s?, Chilton Book Company, 1991, p. 318.
2. ?Waste Management and Resource Recovery?, CRC Press, Inc., Boca Raton, FL 1995, p. 109.
3. Ending Polyethylene Terephthalate's Wild Ride
4. A quote from Waste Recyclers of Tuscaloosa Inc., 907 31st Avenue, Tuscaloosa, Alabama 35401, USA.