Cita APA (7th ed.)

Gratzik, P. (1989). Kohlenkutte. Hinstorff.

Cita Chicago (17th ed.)

Gratzik, Paul. Kohlenkutte. Rostock: Hinstorff, 1989.

Cita MLA (8th ed.)

Gratzik, Paul. Kohlenkutte. Hinstorff, 1989.