在压缩源激发下，真空-弹性表面的精确二维响应。（Garvin问题） 英文描述中有相关参考文献，对于做波场模拟的同学很有用。-THIS FORTRAN PROGRAM CALCULATES THE EXACT SEISMIC 2D RESPONSE FROM A COMPRESSIONAL POINT SOURCE IN AN ELASTIC HALFSPACE WITH A FREE SURFACE. ALL GREEN S FUNCTIONS ARE CALCULATED AN