APA

Burton J. A., Burton P. J. K. & Rignall J. (1973). Owls of the world. New York: Dutton.

Chicago

Burton John A, Burton Philip John Kennedy and Rignall John. 1973. Owls of the world. New York: Dutton.

Harvard

Burton J. A., Burton P. J. K. and Rignall J. (1973). Owls of the world. New York: Dutton.

MLA

Burton John A, Burton Philip John Kennedy and Rignall John. Owls of the world. New York: Dutton. 1973.