A new class of relatively undistorted progressing waves. - V. V. Borisov; Aleksei P. Kiselev (Appl. Math. Lett., 2000)

A Ray Description of All Wavefields Generated by a High-Frequency Point Source near an Interface. - Aleksei P. Kiselev; Alexander S. Starkov; James M. H. Lawry; Vassily M. Babich (SIAM J. Appl. Math., 2001)