KhasanSetiaji, NisaWidyaWardani,Nina Farliana, Muhammad Feriady,DediPurwana. 2020. “Contribution of 21st Century Skills to Work Readiness in Industry 4.0”. International Journal of Advanced Science and Technology 29 (05), 5947 -55. http://sersc.org/journals/index.php/IJAST/article/view/15568.