1. Diffraction of elastic waves by three-dimensional cracks of arbitrary shape in a plane;Glushkov;Prikl. Mat. Mekh.,1996
2. The Space-time Ray Method. Linear and Non-linear Waves;Babich,1985
3. Inverse Acoustic and Electromagnetic Scattering Theory;Colton,1992
4. The Solution of Ill-posed problems;Tikhonov,1979
5. The singularity expansion method;Baum,1976