RyazanovV. I., SrebroU. and YakubovE. (2006) “On the theory of the Beltrami equation”, Ukrains’kyi Matematychnyi Zhurnal, 58(11), pp. 1571–1583. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/3555 (Accessed: 27July2024).