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Klammer, Martin. "Whitman, Slavery, AndThe Emergence of Leaves of Grass."Copyright 1995 The Pennsylvania University.
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Klammer, Martin. "Walt Whitman: An encyclopedia (New York: Garland Publishing, 1998) <whitmanarchive.org/criticism/current/encyclopedia/entry_51.html
Klammer, Martin. "Whitman, Slavery, AndThe Emergence of Leaves of Grass."Copyright 1995 The Pennsylvania University.