Bhargava, R.R., and H.S. Saxena. “Misfitting Elliptic Elastic Inhomogeneity Problem in Perfectly Anisotropic Media”.
Engineering Transactions
, vol. 26, no. 3, June 1978, pp. 381-95,
https://et.ippt.pan.pl/index.php/et/article/view/2132
.