Gaya APA
Guardini, R. (1979).
Sacred Signs, introd. by Melissa Kay. : Von heiligen Zeichen. .
Dublin:
Veritas Publication.
Gaya MLA
Guardini, Romano..
"Sacred Signs, introd. by Melissa Kay. : Von heiligen Zeichen. ".
Dublin:
Veritas Publication,
1979.
Buku.