Daungklang, P., and P. Praneetpolgrang. “QR Code Steganography for Communication in Royal Airforce: An Application”. NKRAFA JOURNAL OF SCIENCE AND TECHNOLOGY, vol. 18, no. 1, June 2022, pp. 15-25, https://ph02.tci-thaijo.org/index.php/nkrafa-sct/article/view/243863.