Scrum: The Art of Doing Twice the Work in Half the Time .schema Book 1 2 3 4author: - Jeff Sutherland - JJ Sutherland url: "http://amzn.to/2Cszaf6" “Scrum” came from Rugby: https://www.google.com/search?q=Rugby+scrum PDCA cycle: Plan, do, check, act Managers remove obstacles.