https://www.avocetta.org/articles/vol-15-12-buv-chick-mortality-and-hatching-asynchrony-in-the-pallidswiftinbspnbspnbsp-apus-pallidusi/
Chick mortality and hatching asynchrony in the Pallid Swift Apus pallidus – Avocetta
Volume 15 - N. 1/2 | Chick mortality and hatching asynchrony in the Pallid Swift Apus pallidus
in thepallid swiftapus palliduschickmortality
https://www.avocetta.org/articles/vol-25-2-vdn-laying-dates-clutch-size-and-breeding-success-in-the-pallid-swift-emapus-pallidusem-in-sofia-bulgaria/
Laying dates, clutch size and breeding success in the Pallid Swift Apus pallidus in Sofia, Bulgaria...
Volume 25 - N. 2 | Laying dates, clutch size and breeding success in the Pallid Swift Apus pallidus in Sofia, Bulgaria
clutch sizein thepallid swiftapus pallidussofia bulgaria