References
- Cramp S. Simmons K. E. L. (Eds.)(1979): Handbook of the Birds of Europe, the Middle East and North Africa. The Birds of the Western Palaearctic. Volume II. Hawks to Bustards. – Oxford, 695 pp.
- RSPB (2002): Owl Pellets: how to study their contents. Wildlife Information Factsheet (12/00). – RSPB. www.rspb.org.uk/teaching/owlpellets/index.asp
- Village A. (1990): The Kestrel. – London.