Cita APA (7a ed.)

Bielefeld, B., & Felsing, O. (1925). Marienburg. O. Felsing.

Cita Chicago Style (17a ed.)

Bielefeld, Bruno, y Otto Felsing. Marienburg. Berlin: O. Felsing, 1925.

Cita MLA (9a ed.)

Bielefeld, Bruno, y Otto Felsing. Marienburg. O. Felsing, 1925.