TY  - BOOK
AU  - Head, George O 
TI  - 1000 autocad tips & tricks / George O. Head & Jan Doster Head.-3rd ed
SN  - 1566040078
U1  - 620.0042 HEA 
CY  - Chapel Hill, NC : Ventana Press, C1993.
KW  - Systems engineering-mathematical models
ER  -