Breeding success of the Black-headed Gull Larus ridibundus in relation to the nesting time

Viksne, J., & Janaus, M. (1980). Breeding success of the Black-headed Gull Larus ridibundus in relation to the nesting time. Ornis Fennica, 57(1), 1–10. Noudettu osoitteesta https://ornisfennica.journal.fi/article/view/133025