"Y. Niwa,S. Hirose","Theoretical analysis of seismic waves in a dipping layer",,"Proc. Japan Soc. Civil Eng.",,"volume 337",,"Page 57-66",1983,Jan. "Y. Niwa,M. Kitahara,S. Hirose","Elastodynamic problems for inhomogeneous bodies",,"Boundary Elements","Springer",,,"Page 751--763",1983,