[1]
Söderholm, S. 2006. Does the Pochard Aythya ferina vary periodically?—an analysis of census data from Angarnsjöängen, Sweden 1978—2003 and Lake Engure, Latvia 1972—1992. Ornis Svecica. 16, 3 (Jul. 2006), 85–94. DOI:https://doi.org/10.34080/os.v16.22712.