George .O. Head, J. D. H. (1992). 1000 AutoCAD Tips & Tricks. Galgotia Publications.
Chicago Style aipamenaGeorge .O. Head, Jan Doster Head. 1000 AutoCAD Tips & Tricks. Galgotia Publications, 1992.
MLA aipamenaGeorge .O. Head, Jan Doster Head. 1000 AutoCAD Tips & Tricks. Galgotia Publications, 1992.
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