De Coy, R. H., & Kahn, R. (1969). Robert H. De Coy's This is progress: The blue book manual of Nigritian history : American descendants of African origin. Nigritian.
Chicago-viite (17. p.)De Coy, Robert H., ja Roselle Kahn. Robert H. De Coy's This Is Progress: The Blue Book Manual of Nigritian History : American Descendants of African Origin. [Los Angeles]: Nigritian, 1969.
MLA-viite (9. p.)De Coy, Robert H., ja Roselle Kahn. Robert H. De Coy's This Is Progress: The Blue Book Manual of Nigritian History : American Descendants of African Origin. Nigritian, 1969.
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