Zulkarnain, Wan Abbas Zakaria, Dwi Haryono, Ktut Murniati. 2020. “Determination of Cost of Sold Goods in Tapioca Factory of Cluster I and Cluster II in Lampung Province”. International Journal of Advanced Science and Technology 29 (04), 5227 -34. http://sersc.org/journals/index.php/IJAST/article/view/25947.