1. Toxicological profile for arsenic and cadmium;Agency for Toxic Substances and Disease Registry (ATSDR),2000
2. ASTM (Annual book of standards) (1981), Proximate Analysis of Coal and Coke, D3172-73, Ultimate Analysis of Coal and Coke, D3176-74, pp. Philadelphia, PA, Part 26, 380; 390-391 and 332 (1978);
3. Forms of Sulphur in Coal, D2492-77 (1981).
4. CEPA (Canadian Environmental Protection Act), (1995). Environment Canada, 1995, Catalogue No. EN21-137/1995E, 1995 (Accessed October 2007).
5. The fate of trace elements in emissions control systems;Carras,1995