APA

Butt (Aune), . (1986). Spotters Guide To 160 Birds Of The British Isles. : .

Chicago

Butt (Aune), . 1986. Spotters Guide To 160 Birds Of The British Isles. : .

Harvard

Butt (Aune), . (1986). Spotters Guide To 160 Birds Of The British Isles. : .

MLA

Butt (Aune), . Spotters Guide To 160 Birds Of The British Isles. : . 1986.