Gupta, Prachi, and Manoj Kumar. “Application of Vigenere Cipher to Enhance the Playfair Cipher Security”. International Journal of Psychosocial Rehabilitation 24, no. 8 (October 31, 2020): 15749–15755. Accessed September 3, 2026. https://psychosocial.com/index.php/ijpr/article/view/12279.