APA (7th ed.) Citation

Flammarion, C. (1905). The unknown. Harper.

Chicago Style (17th ed.) Citation

Flammarion, Camille. The Unknown. New York, NY [u.a.]: Harper, 1905.

MLA (8th ed.) Citation

Flammarion, Camille. The Unknown. Harper, 1905.

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