00318nam a2200121Ia 4500082002100000100001900021245004900040260002700089300001300116490005700129500000500186700000500191  a515.35bSn671.EP  aSneddon, I. N.  aElements of partial differential equationsb  aTokyobKogakushac1957  ax, 327p.  aInternational series in Pure and Applied Mathematics  a  a