1. Regional transport and transformation of sulfur dioxide to sulfates in the United States;Altshuller;Journal of Air Pollution Control Association,1976
2. ASTM (American Society for Testing Materials), 1961. Paper and Paperboard Characteristics, Nomenclature and Significance Test. ASTM Special Technical Publication 60–5, ASTM, 1916 Race St. Philadelphia 3, PA.
3. Heterogeneous reactions of sulfur dioxide with carbonaceous particles;Baldwin;International Journal of Chemical Kinetics,1982
4. On the uncatalized oxidation of atmospheric SO2 by oxygen in aqueous systems;Beilke;Atmospheric Environment,1975
5. CPCB, 2000a. National Ambient Air Quality Status 1998. NAAQM /15/2000-2001 Series of Central Pollution Control Board, Delhi, India.