Cita APA (7a ed.)

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

Cita Chicago Style (17a ed.)

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

Cita MLA (8a ed.)

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