Kim, Young-Soo, and Byoung Yup Lee. “Kerberos System Based Security Model Using Two Factor Authentication for Cloud Computing”. International Journal of Engineering & Technology 7, no. 4.39 (December 13, 2018): 531–534. Accessed May 1, 2024. https://www.sciencepubco.com/index.php/ijet/article/view/24370.