Kristiyani, I.M., and Y. Daryanto. “An Inventory Model Considering All Unit Discount and Carbon Emissions”. International Journal of Industrial Engineering and Engineering Management 1, no. 2 (December 7, 2019): 43–50. Accessed September 1, 2024. https://ojs.uajy.ac.id/index.php/IJIEEM/article/view/3410.