Sihombing, Alfrieldo Josua. “Productivity Analysis And Engineering Of Oil Palm Factory Productivity Process On Boiler Work Effectiveness At PTPN III PKS Sei Mangkei”. Journal Basic Science and Technology 10, no. 2 (February 7, 2022): 60-66. Accessed June 10, 2026. http://ejournal.iocscience.org/index.php/JBST/article/view/1748.