APA

Haffner P., . (1986). Discourses of the popes from Pius XI to John Paul II to the Pontifical Academy of Sciences, 1936-1986. Vatican City: Pontificia Academia Scientiarum.

Chicago

Haffner Paul, . 1986. Discourses of the popes from Pius XI to John Paul II to the Pontifical Academy of Sciences, 1936-1986. Vatican City: Pontificia Academia Scientiarum.

Harvard

Haffner P., . (1986). Discourses of the popes from Pius XI to John Paul II to the Pontifical Academy of Sciences, 1936-1986. Vatican City: Pontificia Academia Scientiarum.

MLA

Haffner Paul, . Discourses of the popes from Pius XI to John Paul II to the Pontifical Academy of Sciences, 1936-1986. Vatican City: Pontificia Academia Scientiarum. 1986.