P. Sudha, A. Lakshmi,. “The Accurate Distance - 2 Domination (Ad-2d) in Graphs”. Mathematical Statistician and Engineering Applications 71, no. 4 (September 17, 2022): 2793–2805. Accessed May 3, 2024. https://www.philstat.org/index.php/MSEA/article/view/837.