Aitken, W. H. M. H. (1894). The Difficulties of the Soul, or Hindrances to Believing. New York.
Čikaški stil citiranja (17. izdanje)Aitken, W. Hay M. H. The Difficulties of the Soul, or Hindrances to Believing. New York, 1894.
MLA način citiranja (8. izdanje)Aitken, W. Hay M. H. The Difficulties of the Soul, or Hindrances to Believing. New York, 1894.
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