Sheikholeslami, Seyed Mahmoud, Rana Khoeilar, and Leila Asgharsharghi. “Signed Strong Roman Domination in Graphs”. Tamkang Journal of Mathematics 48, no. 2 (June 30, 2017): 135-147. Accessed May 24, 2022. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/2240.