W. E. B. Du Bois (2014). “The Problem of the Color Line at the Turn of the Twentieth Century: The Essential Early Essays”, p.220, Oxford University Press
W. E. B. Du Bois, Frederick Douglass, Booker T. Washington (2012). “Three African-American Classics: Up from Slavery, The Souls of Black Folk and Narrative of the Life of Frederick Douglass”, p.329, Courier Corporation