(1940). Key of heaven: A manual of prayers and instructions for Catholics, in accordance with recent pontifical decrees. Catholic Book Pub. Co..
Chicago-viite (17. p.)Key of Heaven: A Manual of Prayers and Instructions for Catholics, in Accordance with Recent Pontifical Decrees. New York: Catholic Book Pub. Co., 1940.
MLA-viite (8. p.)Key of Heaven: A Manual of Prayers and Instructions for Catholics, in Accordance with Recent Pontifical Decrees. Catholic Book Pub. Co., 1940.
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