Osman, B., A. Yasin, and M. N. Omar. “An Analysis of Alphabet-Based Techniques in Text Steganography”. Journal of Telecommunication, Electronic and Computer Engineering (JTEC), vol. 8, no. 10, Dec. 2016, pp. 109-15, https://jtec.utem.edu.my/jtec/article/view/1381.