Aleksandrov Igor Aleksandrovich, Kopanev Sergey Anatol'evich «The problem of estimating the curvature of the level line under conformal mappings of a circle» // Tomsk State University Journal of Mathematics and Mechanics 2013. №6(26) C.5-17
Copanev Sergey Anatol'evich «A note on the curvature of the level line under the conformal mapping» // 2013. № 3(23) C.34-36
