APA Style

Standley, P, C. (1928). Flora of the Panama canal zone. contributions from the United States national herbarium. Vol. 27 (1928) . Washington: U.S. Government Printing Office.

MLA Style

Standley, Paul, C.. "Flora of the Panama canal zone. contributions from the United States national herbarium. Vol. 27 (1928)". Washington: U.S. Government Printing Office, 1928. Digital.