APA-Zitierstil (7. Ausg.)

Hinrichs, G. D. (1875). On the necessity of a physical observatory at the Iowa State University.

Chicago-Zitierstil (17. Ausg.)

Hinrichs, Gustav Dethlef. On the Necessity of a Physical Observatory at the Iowa State University. [S.l.], 1875.

MLA-Zitierstil (9. Ausg.)

Hinrichs, Gustav Dethlef. On the Necessity of a Physical Observatory at the Iowa State University. 1875.