D. G. Harkrider, D. V. Helmberger; A note on nonequivalent quadrupole source cylindrical shear potentials which give equal displacements. Bulletin of the Seismological Society of America ; 68 (1): 125–132. doi:
Two standard integral forms of the cylindrical shear potentials for point quadrupole seismic sources, a frequency domain k-integral and a time domain Cagniardde Hoop path p-integral, are shown not to be the frequency-time domain inverse of each other. Their relationship is derived and they are shown to be seismically equivalent in that they yield the same displacement field.