APA (7th ed.) Citation

Ostenfeld, C. (1898). En Nat paa Jan-Mayen. The Royal Danish Geographical Society.

Chicago Style (17th ed.) Citation

Ostenfeld, C. En Nat Paa Jan-Mayen. The Royal Danish Geographical Society, 1898.

MLA (9th ed.) Citation

Ostenfeld, C. En Nat Paa Jan-Mayen. The Royal Danish Geographical Society, 1898.

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