Ahmed, N., Y. Saleem, H. A. Habib, S. M. Afzal, and S. K. Khurshid. “A Novel Image Encryption Scheme Based on Orthogonal Vectors”. The Nucleus, vol. 52, no. 2, June 2015, pp. 71-78, http://www.thenucleuspak.org.pk/index.php/Nucleus/article/view/652.