APA (7th ed.) Citation

Ilsley, L. C. (1932). Two-hundred-fifty versus 500 volts or more for circuits in gassy coal mines. [publisher not identified].

Chicago Style (17th ed.) Citation

Ilsley, L. C. Two-hundred-fifty Versus 500 Volts or More for Circuits in Gassy Coal Mines. Washington, D.C.: [publisher not identified], 1932.

MLA (9th ed.) Citation

Ilsley, L. C. Two-hundred-fifty Versus 500 Volts or More for Circuits in Gassy Coal Mines. [publisher not identified], 1932.