APA

Gargan E. T., . (1961). Leo XIII and the modern world. New York: Sheed and Ward.

Chicago

Gargan Edward T, . 1961. Leo XIII and the modern world. New York: Sheed and Ward.

Harvard

Gargan E. T., . (1961). Leo XIII and the modern world. New York: Sheed and Ward.

MLA

Gargan Edward T, . Leo XIII and the modern world. New York: Sheed and Ward. 1961.