APA (7th ed.) Citation

Gregory, O., & Wrigley, E. (1973). Read about birds. Wheaton.

Chicago Style (17th ed.) Citation

Gregory, O.B, and Elsie Wrigley. Read About Birds. Great Britain: Wheaton, 1973.

MLA (9th ed.) Citation

Gregory, O.B, and Elsie Wrigley. Read About Birds. Wheaton, 1973.

Warning: These citations may not always be 100% accurate.