Pius XII, P. (1940). The family front: 50th anniversary of Rerum novarum, June 1, 1941. Catholic Worker Press.
Chicago-viite (17. p.)Pius XII, Pope. The Family Front: 50th Anniversary of Rerum Novarum, June 1, 1941. Chicago: Catholic Worker Press, 1940.
MLA-viite (8. p.)Pius XII, Pope. The Family Front: 50th Anniversary of Rerum Novarum, June 1, 1941. Catholic Worker Press, 1940.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.