Citazione Stile APA (7a Edizione)

Pettingill, O. S. (1977). A guide to bird finding east of the Mississippi (2d ed.). Oxford University Press.

Citazione stile Chigago Style (17a edizione)

Pettingill, Olin Sewall. A Guide to Bird Finding East of the Mississippi. 2d ed. New York: Oxford University Press, 1977.

Citatione MLA (9a ed.)

Pettingill, Olin Sewall. A Guide to Bird Finding East of the Mississippi. 2d ed. Oxford University Press, 1977.