A Comparative investigation on Haemochemical factors of Heteropneustes fossilis(Bloch,1797) under the influence of organophosphorus insecticide Malathion(57EC) / [MS Thesis] Fish culture 639.3 COM Thesis (M.Sc.)--Department of Zoology,University of Dhaka,Session : 2002-2003. Includes bibliographical references Dhaka : University of Dhaka, 2007. 2007. 2007 Text viii, 91p. : eng