GB/T606-2003: http://www.instrument.com.cn/show/download/shtml/042344.shtml
GB/T611-2006: http://www.instrument.com.cn/show/download/shtml/050028.shtml
GB/T616-2006: http://www.instrument.com.cn/show/download/shtml/059039.shtml
GB/T11792-89: http://www.instrument.com.cn/show/download/shtml/047502.shtml
GB 6682-1992: http://www.instrument.com.cn/show/download/shtml/059738.shtml
GB/T 9722-2006: http://www.instrument.com.cn/show/download/shtml/040397.shtml