Peterson, Roger Tory, 1908-1996. A field guide to western birds : : field marks of all species found in North America west of the 100th meridian, with a section on the birds of the Hawaiian Islands / [electronic resource] / text and illustrations by Roger Tory Peterson.. — 2nd ed., rev. and enl.. — Boston : : Houghton Mifflin,, c1961.. — xxvi, 309 p., 60 leaves of plates : : ill. (some col.), map ; 19 cm. - The Peterson field guide series ; 2.
"Sponsored by the National Audubon Society and National Wildlife Federation." Each plate preceeded by descriptive text.
Includes bibliographical references (p. xviii-xx) and index.