APA

Bologna G., Bull J. L., . (1981). Simon and Schuster's Guide to birds of the world. New York: Simon and Schuster.

Chicago

Bologna Gianfranco, Bull John L, . 1981. Simon and Schuster's Guide to birds of the world. New York: Simon and Schuster.

Harvard

Bologna G., Bull J. L., . (1981). Simon and Schuster's Guide to birds of the world. New York: Simon and Schuster.

MLA

Bologna Gianfranco, Bull John L, . Simon and Schuster's Guide to birds of the world. New York: Simon and Schuster. 1981.