APA (7th ed.) Citation

Knowlton, F. H. (1889). Fossil wood and lignite of the Potomac formation. Department of the Interior, United States Geological Survey.

Chicago Style (17th ed.) Citation

Knowlton, Frank Hall. Fossil Wood and Lignite of the Potomac Formation. Washington, D.C.: Department of the Interior, United States Geological Survey, 1889.

MLA (9th ed.) Citation

Knowlton, Frank Hall. Fossil Wood and Lignite of the Potomac Formation. Department of the Interior, United States Geological Survey, 1889.

Warning: These citations may not always be 100% accurate.