- Author: Klaus Malling Olsen
- Format: Hardback
- Publisher: A & C Black Publishers Ltd
- Published: 20 September 2004
- ISBN: 9780713670875
The standard text on the identification of the northern hemisphere's gulls, this book covers the plumage variation through age and subspecies of all 80 species in the region. With exhaustive coverage, detailed maps, and superb plates and photos, this book remains the definitive work on these birds, which represent the trickiest of all ID challenges.