Elesin, A., and A. Kadyrova. “Using a Priori Comparative Information in Hydraulic Conductivity Identification Problems”. Numerical Methods and Programming (Vychislitel’nye Metody I Programmirovanie), vol. 9, no. 15, Dec. 2007, pp. 10-15, https://en.num-meth.ru/index.php/journal/article/view/290.