Richards, J. (2013). Freehand drawing and discovery: Urban sketching and concept drawing for designers. Wiley.
Chicago-viite (17. p.)Richards, James. Freehand Drawing and Discovery: Urban Sketching and Concept Drawing for Designers. Hoboken, New Jersey: Wiley, 2013.
MLA-viite (8. p.)Richards, James. Freehand Drawing and Discovery: Urban Sketching and Concept Drawing for Designers. Wiley, 2013.
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