Rendite radikal steigern, Frankfurt / Main, 2000 ^ Stamatis, D. H. (2004). Six Sigma Fundamentals: A Complete Guide to the System, Methods, and Tools . New York, New York : Productivity Press. p. 1. ISBN   978-1-56327-292-9 . OCLC   52775178 . "The practitioner of the six sigma methodology in any organization should expect to