Gaya APA
Syukron, A., Kholik, M.
(2013).
Six sigma : quality for business improvement
.
Yogyakarta:
Graha Ilmu.
Gaya MLA
Syukron, Amin., Kholik, Muhammad.
"Six sigma : quality for business improvement".
Yogyakarta:
Graha Ilmu,
2013.
Text.