Computation of the second term of the ray method series in two and a half dimension

The algorithm of computation of the second term of the ray method series suggested in our paper in the present issue is specified for the case of two and a half dimensions. It means that elastic parameters of a medium depend on $x,z$ only and source and observation points are placed in one plane orthogonal to $y$ axes. Thus to compute the wave field we need to take into account the rays which are placed in the plane. It enables us to simplify the algorithm. We consider the algorithm in detail for the case of the point source. Bibliography: 4 titles.