et. al., Oktora Yogi Sari,. “Quality Control Analysis Using Statistical Procces Control (Spc) To Reduce Product Defects In Roastery X”. Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, no. 8 (April 24, 2021): 1555–1562. Accessed May 6, 2024. https://turcomat.org/index.php/turkbilmat/article/view/3204.