APA (7th ed.) Citation

United States. Weather Bureau. (1960). Climates of the states: Pennsylvania. U.S. G.P.O..

Chicago Style (17th ed.) Citation

United States. Weather Bureau. Climates of the States: Pennsylvania. Washington, D.C.: U.S. G.P.O., 1960.

MLA (9th ed.) Citation

United States. Weather Bureau. Climates of the States: Pennsylvania. U.S. G.P.O., 1960.