Willging, E. P. (1937). The Index to American Catholic pamphlets. Catholic Library Service.
Chicago Style aipamenaWillging, Eugene P. The Index to American Catholic Pamphlets. [Saint Paul, Minn.: Catholic Library Service, 1937.
MLA aipamenaWillging, Eugene P. The Index to American Catholic Pamphlets. Catholic Library Service, 1937.
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