Gaya APA

Guardini, R. (2005). Romano Guardini: Spiritual writings. Selected, transl. & introd. by Robert A. Krieg. . New York: New York Orbis Books.

Gaya MLA

Guardini, Romano. "Romano Guardini: Spiritual writings. Selected, transl. & introd. by Robert A. Krieg. ". New York: New York Orbis Books, 2005. Buku.