1. Ambient Air Quality Standards, 40 CFR 50, Government Printing Office, Washington, DC, 1981.
2. Pollution Engineering;J Matey,1982
3. Commission on Natural Resources. 1981. On Prevention of Significant Deterioration of Air Quality, Washington, DC: Government Printing Office, 1981.
4. Pollution Engineering;T Sweitzer,1980
5. Waste Age;C Gunther,1981