APA-viite (7. p.)

Catholic Church. Pope (1963-1978 : Paul VI). (1968). Encyclical letter of his Holiness Pope Paul VI: On the regulation of birth : Humanae vitae, issued July 25, 1968. St. Paul Editions.

Chicago-viite (17. p.)

Catholic Church. Pope (1963-1978 : Paul VI). Encyclical Letter of His Holiness Pope Paul VI: On the Regulation of Birth : Humanae Vitae, Issued July 25, 1968. Boston, Mass.: St. Paul Editions, 1968.

MLA-viite (8. p.)

Catholic Church. Pope (1963-1978 : Paul VI). Encyclical Letter of His Holiness Pope Paul VI: On the Regulation of Birth : Humanae Vitae, Issued July 25, 1968. St. Paul Editions, 1968.