Anusha, M., V. Kavitha, S. P. Lekhana, M. S. Sahana, and A. Sushma. “Multilevel Authentication Sing OTP, QR-Code and Hadamard Transformation”. International Journal of Research in Engineering, Science and Management 3, no. 8 (August 4, 2020): 44–46. Accessed December 21, 2024. https://journal.ijresm.com/index.php/ijresm/article/view/120.