Lidwell, W., & Holden, K. (2003). Universal principles and design. Rockport Publishers.
Lua i Stíl Chicago (17ú heag.)Lidwell, Wiliiam, agus Kritina Holden. Universal Principles and Design. Beverly, Massachusetts: Rockport Publishers, 2003.
Lua MLA (9ú heag.)Lidwell, Wiliiam, agus Kritina Holden. Universal Principles and Design. Rockport Publishers, 2003.
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