One from the first authors that men

One from the first authors that mentioned success factors for Six Sigma is
Harry in, 2000. The CSF which will be referred in the current study, are implemented
in service firms and industries, and in small, medium and bigger size companies
as well. What differs is the degree of the importance of the factor according to the kind
of organization. Factors are referred with different expressions and manners in
bibliography, but there was an effort to report all of them and as an author is
mentioned the first one that recorded it.