APA Style

Klots, A, B. (1951 (renewed 1979)). A Field Guide to the Butterflies of North America, East of the Great Plains (Peterson Field Guide Series edition). Boston, Massachusetts, USA: HOUGHTON MIFFLIN COMPANY.

MLA Style

Klots, Alexander, B.. "A Field Guide to the Butterflies of North America, East of the Great Plains". Peterson Field Guide Series edition Boston, Massachusetts, USA: HOUGHTON MIFFLIN COMPANY, 1951 (renewed 1979). BOOK.