Freedman, R. (2012). Abraham Lincoln and Frederick Douglass: The story behind an American friendship. Houghton Mifflin Harcourt/Clarion Books.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रFreedman, Russell. Abraham Lincoln and Frederick Douglass: The Story Behind an American Friendship. Boston: Houghton Mifflin Harcourt/Clarion Books, 2012.
एमएलए (8वां संस्करण) प्रशस्ति पत्रFreedman, Russell. Abraham Lincoln and Frederick Douglass: The Story Behind an American Friendship. Houghton Mifflin Harcourt/Clarion Books, 2012.
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