A. Gheriballah, and R. Rouane. “Note on Nonparametric \(M\)-Estimation for Spatial Regression”. Malaya Journal of Matematik 2, no. 01 (January 1, 2014): 35–42. Accessed July 16, 2024. https://www.malayajournal.org/index.php/mjm/article/view/389.