1. Handbook of the Birds of Europe, the Middle East and North Africa: The Birds of the Western Palearctic, vols. I and II.;Cramp,1980
2. The Vortex of Life.;Edwards,1993
3. A Field Guide to the Nests, Eggs and Nestlings of British and European birds.;Harrison,1975
4. The Birds.;Peterson,1967
5. The shapes of birds' eggs: Mathematical aspects.;Preston;Auk,1968