Russwurm, N. (1937). Rev. Paul Joseph Volk: A pioneer missionary in two continents. St. Bernard Abbey.
Chicago-viite (17. p.)Russwurm, Norbert. Rev. Paul Joseph Volk: A Pioneer Missionary in Two Continents. St. Bernard, Ala.: St. Bernard Abbey, 1937.
MLA-viite (8. p.)Russwurm, Norbert. Rev. Paul Joseph Volk: A Pioneer Missionary in Two Continents. St. Bernard Abbey, 1937.
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