Writers' Program. Pa. (1940). Pennsylvania: A guide to the Keystone state. Oxford university press.
Chicago Style (17th ed.) CitationWriters' Program. Pa. Pennsylvania: A Guide to the Keystone State. New York: Oxford university press, 1940.
MLA (9th ed.) CitationWriters' Program. Pa. Pennsylvania: A Guide to the Keystone State. Oxford university press, 1940.
Warning: These citations may not always be 100% accurate.