Ray Theory for High-Péclet-Number Convection-Diffusion. - S. Jonathan Chapman; James M. H. Lawry; John R. Ockendon (SIAM J. Appl. Math., 1999)

On the Theory of Complex Rays. - S. Jonathan Chapman; James M. H. Lawry; John R. Ockendon; Richard H. Tew (SIAM Rev., 1999)

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)