Heylen, L. (1865). The progress of the age, and the danger of the age: Two lectures delivered before the St. Xavier Conference of the St. Vincent de Paul Brotherhood in the hall of St. Louis University. J. P. Walsh.
Chicago-viite (17. p.)Heylen, Louis. The Progress of the Age, and the Danger of the Age: Two Lectures Delivered Before the St. Xavier Conference of the St. Vincent De Paul Brotherhood in the Hall of St. Louis University. Cincinnati: J. P. Walsh, 1865.
MLA-viite (8. p.)Heylen, Louis. The Progress of the Age, and the Danger of the Age: Two Lectures Delivered Before the St. Xavier Conference of the St. Vincent De Paul Brotherhood in the Hall of St. Louis University. J. P. Walsh, 1865.
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