Henry David Thoreau, Jeffrey S. Cramer (2007). “I to Myself: An Annotated Selection from the Journal of Henry D. Thoreau”, p.353, Yale University Press
Henry David Thoreau (2014). “Citizen Thoreau: Walden, Civil Disobedience, Life Without Principle, Slavery in Massachusetts, A Plea for Captain John Brown”, p.16, Graphic Arts Books