S. A. Hosseiny Motikolai, A. H. Kamalyan, and M. I. . Karakhanyan, “ON AN ANISOTROPIC BOUNDARY PROBLEM OF DIFFRACTION WITH FIRST AND SECOND TYPE BOUNDARY CONDITIONS”, Proc. YSU A: Phys. Math. Sci., vol. 44, no. 2 (222), pp. 12–15, Apr. 2010.