Bachhav , Monali, Ashutosh Sharad Kale, Siddhant Santosh Daule , and Pradnya Dhanraj Bikkad . 2025. “Payoff: Secure Offline Payment System Using Bluetooth and Block-Chain”. International Journal of Recent Advances in Engineering and Technology 14 (1s):226-28. https://journals.mriindia.com/index.php/ijraet/article/view/280.