APA-referens (7:e uppl.)

Keller, P. A. (2005). Six sigma demystified. McGraw-Hill.

Chicago-referens (17:e uppl.)

Keller, Paul A. Six Sigma Demystified. New York: McGraw-Hill, 2005.

MLA-referens (8:e uppl.)

Keller, Paul A. Six Sigma Demystified. McGraw-Hill, 2005.