RT Journal Article SR Electronic(1) A1 Zillmer, M. A1 M. Kashtan, B. A1 Gajewski, D.YR 1998 T1 Quasi-Isotropic Approximation and Coupling Ray Theory JF , VO OP SP cp-110-00327 DO https://doi.org/10.3997/2214-4609.201408426 PB European Association of Geoscientists & Engineers, SN 2214-4609, AB , UL https://www.earthdoc.org/content/papers/10.3997/2214-4609.201408426