APA (7th ed.) Citation

(1919). Polens Kohlenbergbau. Hempel.

Chicago Style (17th ed.) Citation

Polens Kohlenbergbau. Berlin: Hempel, 1919.

MLA (8th ed.) Citation

Polens Kohlenbergbau. Hempel, 1919.

Warning: These citations may not always be 100% accurate.