What signs indicate a successful continuous improvement culture
http://www.industryweek.com/operations/what-signs-indicate-i-am-successfully-building-continuous-improvement-culture
http://www.industryweek.com/operations/what-signs-indicate-i-am-successfully-building-continuous-improvement-culture
https://www.qualitydigest.com/inside/six-sigma-article/sick-sigma.html