Cita APA (7a ed.)
Peterson, R. T. (1941). A FIELD GUIDE TO WESTERN BIRDS.
Cita estilo Chicago (17a ed.)
Peterson, Roger Tory. A FIELD GUIDE TO WESTERN BIRDS. 1941.
Cita MLA (9a ed.)
Peterson, Roger Tory. A FIELD GUIDE TO WESTERN BIRDS. 1941.
Precaución: Estas citas no son 100% exactas.