Cita APA (7a ed.)

Bielfeldt, A., & Walsemann, E. (1912). Altonaer Stadtkalender. Hammerich & Lesser.

Cita Chicago Style (17a ed.)

Bielfeldt, August, y Edgar Walsemann. Altonaer Stadtkalender. Altona: Hammerich & Lesser, 1912.

Cita MLA (8a ed.)

Bielfeldt, August, y Edgar Walsemann. Altonaer Stadtkalender. Hammerich & Lesser, 1912.