text Groningen University of Groningen 1991 Ind 143 p. : ill. ; 24 cm.-- 143 p. : ill. ; 24 cm.-- SWENNEN, Cornelis DUCKS ANIMAL ECOLOGY POPULATION CHANGE NETHERLAND 598.412(492)_ 598.412SWEe INLIS000000000002593 Converted from MARCXML to MODS version 3.5 using MARC21slim2MODS3-5.xsl (Revision 1.106 2014/12/19)