Cheng-Tan Tung , Shu-Cheng Lin , Peterson Julian. “Note on Lexicographical Ordering”. International Journal of Emerging Trends in Science and Technology 4, no. 05 (May 30, 2017): 5165–5170. Accessed January 31, 2025. http://igmpublication.com/ijetst.in/index.php/ijetst/article/view/1101.