APA (7th ed.) Citation

Arnold, C. A. (1940). Lepidodendron johnsonii, sp. nov., from the lower Pennsylvanian of central Colorado. University of Michigan Press.

Chicago Style (17th ed.) Citation

Arnold, Chester A. Lepidodendron Johnsonii, Sp. Nov., from the Lower Pennsylvanian of Central Colorado. Ann Arbor: University of Michigan Press, 1940.

MLA (9th ed.) Citation

Arnold, Chester A. Lepidodendron Johnsonii, Sp. Nov., from the Lower Pennsylvanian of Central Colorado. University of Michigan Press, 1940.