1. Clutch size in the Long-tailed Skua Stercorarius longicaudus: some field experiments;Andersson;Env. Biol. Fish.,1976
2. Effects of addition and removal of nestlings on nestling weight, nestling survival and female weight loss in the Pied Flycatcher Ficedula hypoleuca (Pallas);Askemo;Ornis Scand,1977
3. Askemo , C. Reproductive effort and the survival rate of male Pied Flycatchers
4. Breeding biology of the House Martin Delichon urbica in relation to insect abundance;Bryant;Ornis Scand,1975
5. On clutch size and fitness;Charnov;Ornis Scand.,1974