Field guide to the birds of Britain and Europe. - 5th edition / in collaboration with D.I.M. Wallace. - Boston : Houghton Mifflin Company, ©1993. - (The Peterson field guide series®). - Oorspronkelijke uitgave: London : HarperCollins, ©1954

Field guide to the birds of Britain and Europe. - 5th edition / in collaboration with D.I.M. Wallace. - Boston : Houghton Mifflin Company, ©1993. - (The Peterson field guide series®). - Oorspronkelijke uitgave: London : HarperCollins, ©1954