Les writes in to suggest The Complete Technical Illustrator by Jon Duff and Greg Maxson.
It covers detailed step-by-step information on how to go about creating technical illustrations in Adobe Illustrator […] using standard isometric, dimetric, trimetric, and perspective views, using step-by-step details about how to setup the view and how to create and position ellipses and other object correctly based on the view. The book covers how to create correct and compelling line illustrations, and later, how to apply color and shading for realistic looks. The book also covers illustration techniques using 3ds Max and AutoCAD, but most of the book is focuses on Adobe Illustrator.
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