Studies in Mathematics and its Applications

STUDIES IN MATHEMATICS AND ITS APPLICATIONS

VOLUME 33

Editors: D.N. ARNOLD, Minnisota P.G. CIARLET, Hong Kong and Paris P.L. LIONS, Paris H.A. VAN DER VORST, Utrecht Editors Emeriti: H. FUJITA, Tokyo H.B. KELLER, Pasadena J.L. LIONS• , Paris G. PAPANICOLAOU, New York

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