Study on the development of the Gadwall Anas strepera Linnaeus, in captivity (with observations on daily activities, behaviour and food preferences) / [MS Thesis] Anas Ducks 598.413 STU Thesis (MS )—Department of Zoology, University of Dhaka, Session : 1993-94. Includes bibliographical references. Dhaka : University of Dhaka, 1997. 1997. 1997 Text ix, 126 p. : eng