6Ning Jing-feng, Chen Zhi-yu,Liu Gang. PDCA process ap-plication in the continuous improvement of software quality[C]. USA;Control and Electronic Engineering,2010;61 -65.
7ShiYong-kui,Song Guo-feng. Process control system of roofdisaster based on PDCA cycle [ C] . USA: Industrial Engi-neering and Engineering Management, 2009 : 199-203.