APA (7th ed.) Citation

Pilger, T. (1925). German pulverized coal internal combustion engine. [publisher not identified].

Chicago Style (17th ed.) Citation

Pilger, Theodore. German Pulverized Coal Internal Combustion Engine. Washington, D.C.: [publisher not identified], 1925.

MLA (9th ed.) Citation

Pilger, Theodore. German Pulverized Coal Internal Combustion Engine. [publisher not identified], 1925.