APA (7th ed.) Citation

Barnes, J. H., & Smith, R. C. (2001). The nonfuel mineral resources of Pennsylvania. Pennsylvania Geological Survey.

Chicago Style (17th ed.) Citation

Barnes, John Henry, and Robert Charles Smith. The Nonfuel Mineral Resources of Pennsylvania. Harrisburg, Pa.: Pennsylvania Geological Survey, 2001.

MLA (9th ed.) Citation

Barnes, John Henry, and Robert Charles Smith. The Nonfuel Mineral Resources of Pennsylvania. Pennsylvania Geological Survey, 2001.