00266nam a2200109Ia 4500082001900000100002300019245004300042260004800085300001300133500000500146700000500151  a530.1bF911.WE  aFriedlander, F. G.  aWave equation on a curved space timeb  aCambridgebCambridge University Pressc1975  ax, 282p.  a  a