Toxicity of copper sulphate (CuSO4 5H2O) to shingi fish, Heteropneustes fossilis (Bloch) : lethal doses and histopathological aspects / [MS Thesis] Fishes 597.2 TOX Thesis (MS )--Department of Zoology, University of Dhaka, Session : 2006-2007. Includes bibliographical references. Dhaka : University of Dhaka, 2009. 2009. 2009 Text viii, 75 p. : eng