Rachmatullah, R., Kasih, T. P., & Purba, H. H. (2015). The Effect of 5K2S Implementation to the Opportunities of Increasing Productivity and Workplace Improvement in PT. Andesen Jaya Plastik. ComTech: Computer, Mathematics and Engineering Applications, 6(4), 590-603. https://doi.org/10.21512/comtech.v6i4.2197