APA
Leo XIII P., . (1941). The chief duties of christians as citizens : encyclical letter of Pope Leo XIII. New York: The Paulist Press.
Chicago
Leo XIII Pope, . 1941. The chief duties of christians as citizens : encyclical letter of Pope Leo XIII. New York: The Paulist Press.
Harvard
Leo XIII P., . (1941). The chief duties of christians as citizens : encyclical letter of Pope Leo XIII. New York: The Paulist Press.
MLA
Leo XIII Pope, . The chief duties of christians as citizens : encyclical letter of Pope Leo XIII. New York: The Paulist Press. 1941.
