Two-dimensional inverse problem for wave equation, the uniqueness in regularizating statemen

Inverse problem for wave equation with instant, lagging source on segment of boundary y=0 is considered. The problem of determination of sound velocity, smooth depending of both spacing coordinates by response of medium on the same segment, is posed. In regularizating statement the uniqueness of problem is proved with assumption of eikonal regularity. Regularization consists in addition to wave operator the operator of higher degree with small parameter.