APA (7th ed.) Citation

Paul, J. W., & Plein, L. N. (1931). Study of falls of roof and coal in mines in number 8 field of eastern Ohio. [publisher not identified].

Chicago Style (17th ed.) Citation

Paul, J. W., and Leopold Nicholas Plein. Study of Falls of Roof and Coal in Mines in Number 8 Field of Eastern Ohio. Washington, D.C.: [publisher not identified], 1931.

MLA (9th ed.) Citation

Paul, J. W., and Leopold Nicholas Plein. Study of Falls of Roof and Coal in Mines in Number 8 Field of Eastern Ohio. [publisher not identified], 1931.