1. Standard methods for the examinations of water and wastewater;APHA,1980
2. Marine pollution and marine waste disposal;Bernhard,1975
3. The oxygen requirements of activated sludge determined by manometric methods II;Dawson;Sewage Industr. Wastes,1950
4. The effect of zinc, lead and cadmium pollution on the leaf surface of microflora;Gingell;J. of Env. Pollution,1976
5. Effect of copper and lead bearing wastes on purification of sewage;Kalabina;Water & Sewage Works,1946