Richards, J. (2013). Freehand drawing and discovery: Urban sketching and concept drawing for designers. Wiley.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रRichards, James. Freehand Drawing and Discovery: Urban Sketching and Concept Drawing for Designers. Hoboken, New Jersey: Wiley, 2013.
एमएलए (8वां संस्करण) प्रशस्ति पत्रRichards, James. Freehand Drawing and Discovery: Urban Sketching and Concept Drawing for Designers. Wiley, 2013.
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