8Smith S W, Making J D. Control chart work for you[J]. Semiconductor International, 1991,14( 1 ) :86 - 89
9Hamada M, Mackay R J, Whitney J B. Continuous process improvement with observational studies [ J ]. Journal of Quality Technology, 1993,25(2) :77 - 83
10Yashchin E. Monitoring variance components[ J]. Technometrics, 1994,36(4) :379 -393