Cita APA (7th ed.)

Peterson, R. T. (1956). A fiels guide to the birds (2ª ed.). Houghton Miffin Company.

Cita Chicago (17th ed.)

Peterson, Roger Tory. A Fiels Guide to the Birds. 2ª ed. Houghton Miffin Company, 1956.

Cita MLA (9th ed.)

Peterson, Roger Tory. A Fiels Guide to the Birds. 2ª ed. Houghton Miffin Company, 1956.