The AutoCAD book : drawing, modeling, and applications using AutoCAD 2004 - Kirkpatrick, James M. 4 0 16; 5 (Upper Saddle River, New Jersey; Columbus, Ohio :;Upper Saddle River, NJ : Pearson / Prentice Hall,;Pearson Prentice Hall, 2004)
Keywords: 2 -- 0; 6; 20; 20; 2