00398cam0a2200133i004500001000500000005001700005020001500022035001500037041001100052100002000063245007500083260007900158300002700237155420260715153158.0  a9022003531  atr986004690 aengger1 aKaltofen, R. S.10aEmbryonic development in the eggs of the Pekin Duck /cR. S. Kaltofen.  aWageningen :bCentre for Agricultural Publishing and Documentation,c1971.  a72 s. :bil. ;c17 cm.