Goncharsky, A., S. Romanov, and S. Kharchenko. “The Inverse Problem of Acoustic Diagnosis for Three-Dimensional Media”. Numerical Methods and Programming (Vychislitel’nye Metody I Programmirovanie), vol. 7, no. 7, Apr. 2006, pp. 113-21, https://en.num-meth.ru/index.php/journal/article/view/199.