APA
Pius XII P., . (1948). Christian worship: Encyclical letter. London: .
Chicago
Pius XII Pope, . 1948. Christian worship: Encyclical letter. London: .
Harvard
Pius XII P., . (1948). Christian worship: Encyclical letter. London: .
MLA
Pius XII Pope, . Christian worship: Encyclical letter. London: . 1948.
