Cita APA (7th ed.)
Frank, J. (1920). Zur Geschichte des Astrolabs.
Cita Chicago (17th ed.)
Frank, Josef. Zur Geschichte Des Astrolabs. Erlangen, 1920.
Cita MLA (9th ed.)
Frank, Josef. Zur Geschichte Des Astrolabs. 1920.
Atenció: Aquestes cites poden no estar 100% correctes.