Keedy, Jeffrey. "The Rules of Typography According to Crackpots Experts." Looking Closer: Critical Writings on Graphic Design, Vol. 3 Ed. Bierut, Michael, William Drettnel, Steven Heller and DK Holland. New York: Allsworth Press, 1997. Web.

Foss, Sonja K., Karen A. Foss, and Robert Trapp. "An Introduction to Rhetoric." Perspectives on Rhetoric (3rd Ed.). PDF.

Lanham, Richard. The Economics of Attention. Chicago: University of Chicago Press, 2006. PDF.