KozachenkoY. V., and KurchenkoО. O. “Estimation of Parameters of Homogeneous Gaussian Random Fields”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 52, no. 8, Aug. 2000, pp. 1082-8, https://umj.imath.kiev.ua/index.php/umj/article/view/4511.