@article{Burskii_Lesina_2012, title={Neumann problem and one oblique-derivative problem for an improperly elliptic equation}, volume={64}, url={https://umj.imath.kiev.ua/index.php/umj/article/view/2589}, abstractNote={We investigate the solvability of an inhomogeneous Neumann problem and oblique-derivative problem for an improperly elliptic scalar differential equation with complex coefficients in a bounded domain. The model case where the domain is the unit disk and the equation does not have lower-order terms is studied. It is proved that the classes of boundary data for which the problems have unique solutions in a Sobolev space are the spaces of functions with exponentially decreasing Fourier coefficients.}, number={4}, journal={Ukrains’kyi Matematychnyi Zhurnal}, author={Burskii, V. P. and Lesina, E. V.}, year={2012}, month={Apr.}, pages={451-462} }