Cita APA (7a ed.)

Marbach, O. (1864). Proteus. [s.n.].

Cita Chicago Style (17a ed.)

Marbach, Oswald. Proteus. Leipzig: [s.n.], 1864.

Cita MLA (9a ed.)

Marbach, Oswald. Proteus. [s.n.], 1864.