Litterae encyclicae "summi pontificatus". 20 oct. 1939.

MLA

Aguirre. Litterae Encyclicae "summi Pontificatus". 20 Oct. 1939. Roma: Tip. Univ. Gregorianna, 1939.

APA

Aguirre, A. (1939). Litterae encyclicae "summi pontificatus". 20 oct. 1939. Roma: Tip. Univ. Gregorianna.

Chicago

Aguirre Litterae Encyclicae "summi Pontificatus". 20 Oct. 1939: . Roma: Tip. Univ. Gregorianna, 1939.