APA

Gruson E. S., Forster R. A., . (1976). Checklist of the world's birds: a complete list of the species, with names, authorities, and areas of distribution. New York: Quadrangle/New York Times Book Co.

Chicago

Gruson Edward S, Forster Richard A, . 1976. Checklist of the world's birds: a complete list of the species, with names, authorities, and areas of distribution. New York: Quadrangle/New York Times Book Co.

Harvard

Gruson E. S., Forster R. A., . (1976). Checklist of the world's birds: a complete list of the species, with names, authorities, and areas of distribution. New York: Quadrangle/New York Times Book Co.

MLA

Gruson Edward S, Forster Richard A, . Checklist of the world's birds: a complete list of the species, with names, authorities, and areas of distribution. New York: Quadrangle/New York Times Book Co. 1976.