APA (7th ed.) Citation

Clegg, K. E. (1965). Subsurface geology and coal resources of the Pennsylvanian system in Clark, and Edgar Counties, Illinois. [publisher not identified].

Chicago Style (17th ed.) Citation

Clegg, Kenneth Edward. Subsurface Geology and Coal Resources of the Pennsylvanian System in Clark, and Edgar Counties, Illinois. Urbana: [publisher not identified], 1965.

MLA (9th ed.) Citation

Clegg, Kenneth Edward. Subsurface Geology and Coal Resources of the Pennsylvanian System in Clark, and Edgar Counties, Illinois. [publisher not identified], 1965.