2Shyr-Long Jeng,etc. Modeling and diagnosis of motion error of multi-axis machines using a ball bar test[J]. Journal of dynamic systemes, measurement,and control, 1996, 18(9):531.
7Anthony Chukwujekwu Okafor,Yalcin M Ertekin.Vertical machining center accuracy characterization using laser interferometer[J]. Journal of Materials Processing Tech. . 2000 (3)