Cita APA (7th ed.)

Ferber, W. (1973). Romano Guardini: Walter Ferber. Aschendorff.

Cita Chicago (17th ed.)

Ferber, Walter. Romano Guardini: Walter Ferber. Münster: Aschendorff, 1973.

Cita MLA (8th ed.)

Ferber, Walter. Romano Guardini: Walter Ferber. Aschendorff, 1973.