APA (7th ed.) Citation

Hagen, E. A. (1897). August Hagen. [s.n.].

Chicago Style (17th ed.) Citation

Hagen, Ernst August. August Hagen. Berlin: [s.n.], 1897.

MLA (9th ed.) Citation

Hagen, Ernst August. August Hagen. [s.n.], 1897.

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