Quilala, Rogel Ladia, Ariel M Sison, and Ruji P Medina. “QR Code Integrity Verification Based on Modified SHA-1 Algorithm”. Indonesian Journal of Electrical Engineering and Informatics (IJEEI) 6, no. 4 (December 25, 2018): 385–392. Accessed October 28, 2026. https://section.iaesonline.com/index.php/IJEEI/article/view/494.