APA (7th ed.) Citation

Peerless Coal Co & Howard, R. (1930). Driving rock slopes at new Peerless mine. [publisher not identified].

Chicago Style (17th ed.) Citation

Peerless Coal Co and Robert Howard. Driving Rock Slopes at New Peerless Mine. Washington, D.C.: [publisher not identified], 1930.

MLA (9th ed.) Citation

Peerless Coal Co and Robert Howard. Driving Rock Slopes at New Peerless Mine. [publisher not identified], 1930.