Gaya APA
EVANS, J, R. et al (2007).
An introduction to six sigma a & process improvement = pengantar six sigma .
Jakarta:
Salemba Empat.
Gaya MLA
EVANS, James, R.. et al.
"An introduction to six sigma a & process improvement = pengantar six sigma".
Jakarta:
Salemba Empat,
2007.
Buku.