00332nam a2200121Ia 4500082002300000100003200023245002800055260002700083300002600110490006400136500000500200700000500205  a658.4033bAv963.GC  aZvriel, Mordecai and Others  aGeneralized concavityb  aNew YorkbPlenumc1988  ax, 332p. Index, Bibl.  aMathematical concepts and methods in Science and Engg. v.36  a  a