Wibowo, Santo, and Humiras Hardi Purba. “Improving Defect Tire Curing Process With Six Sigma Method at Tire Manufacturing Industry”. Proceeding Mercu Buana Conference on Industrial Engineering, vol. 1, no. 1, Jan. 2019, pp. 20-27, https://training-ojs3-publikasi.mercubuana.ac.id/index.php/mbcie/article/view/20318.