Gaya APA
PURBA, H, H., AIYASAH, S. (2017).
QUALITY IMPROVEMENT AND LEAN SIX SIGMA (1).
Yogyakarta:
Android Community Experts.
Gaya MLA
PURBA, HUMIRAS, HARDI., AIYASAH, SITI.
"QUALITY IMPROVEMENT AND LEAN SIX SIGMA".
1
Yogyakarta:
Android Community Experts,
2017.
Text.