Northrop, H. D., Penn, I. G. 1., & Gay, J. R. (1900). The college of life or, Practical self-educator: A manual of self-improvement for the colored race ... giving examples and achievements of successful men and women of the race ... including Afro-American progress. [S.l.: s.n.].

Northrop, Henry Davenport, I. Garland 1867-1930 Penn, and Joseph R. Gay. The College of Life Or, Practical Self-educator: A Manual of Self-improvement for the Colored Race ... Giving Examples and Achievements of Successful Men and Women of the Race ... Including Afro-American Progress. [S.l.: s.n.], 1900.

Northrop, Henry Davenport, I. Garland 1867-1930 Penn, and Joseph R. Gay. The College of Life Or, Practical Self-educator: A Manual of Self-improvement for the Colored Race ... Giving Examples and Achievements of Successful Men and Women of the Race ... Including Afro-American Progress. [S.l.: s.n.], 1900.