Lidwell, W., Holden, K., & Butler, J. (2010). Universal principles of design. Rockport Publishers.
Chicago Style (17th ed.) ZitazioaLidwell, William, Kritina Holden, eta Jill Butler. Universal Principles of Design. Beverly, Mass.: Rockport Publishers, 2010.
MLA (9th ed.) ZitazioaLidwell, William, et al. Universal Principles of Design. Rockport Publishers, 2010.
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