Cita APA (7th ed.)

Freksa, F., & Preetorius, E. (1912). Phosphor. Georg Müller.

Cita Chicago (17th ed.)

Freksa, Friedrich, i Emil Preetorius. Phosphor. München: Georg Müller, 1912.

Cita MLA (8th ed.)

Freksa, Friedrich, i Emil Preetorius. Phosphor. Georg Müller, 1912.