Gaya APA

Guardini, R. (1985). The art of praying: The priciples and methods of Christian prayer. : Vorschule des Betens. . Manchester: Manchester Sophia Institute Press.

Gaya MLA

Guardini, Romano. "The art of praying: The priciples and methods of Christian prayer. : Vorschule des Betens. ". Manchester: Manchester Sophia Institute Press, 1985. Buku.