00317nam a2200121Ia 4500082002100000100002300021245005600044260003100100300001600131490003800147500000500185700000500190  a515.73bAu894.AE  aAubin, Jean Pierre  aApproximation of elliptic boundary value problemsb  aNew YorkbJohn Wileyc1972  axvii, 360p.  aPure and Applied Mathematicsv 26  a  a