Brussee, W. (2005). All About six sigma. [TMH.
Lua i Stíl Chicago (17ú heag.)Brussee, Warren. All About Six Sigma. [s.l]: [TMH, 2005.
Lua MLA (9ú heag.)Brussee, Warren. All About Six Sigma. [TMH, 2005.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.