APA (7th ed.) Citation

Metzger, O. H. (1937). Aerial tramways in the metal mining industry. United States Bureau of Mines. Information Circular, 6948, 1.

Chicago Style (17th ed.) Citation

Metzger, O. H. "Aerial Tramways in the Metal Mining Industry." United States Bureau of Mines. Information Circular 6948 (1937): 1.

MLA (9th ed.) Citation

Metzger, O. H. "Aerial Tramways in the Metal Mining Industry." United States Bureau of Mines. Information Circular, vol. 6948, 1937, p. 1.