Duffy, M. J., Gasnick, R. M., & Francis, o. A. (1980). Francis, brother of the universe: His complete life's story. Marvel Comics Group : Franciscan Communications Office.
Chicago-viite (17. p.)Duffy, Mary Jo, Roy M. Gasnick, ja of Assisi Francis. Francis, Brother of the Universe: His Complete Life's Story. New York: Marvel Comics Group : Franciscan Communications Office, 1980.
MLA-viite (8. p.)Duffy, Mary Jo, et al. Francis, Brother of the Universe: His Complete Life's Story. Marvel Comics Group : Franciscan Communications Office, 1980.
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