00300nam a2200121Ia 4500082001700000100001800017245004100035260002500076300002600101490004100127500000500168700000500173  a516bG449.SP  aGibson, C. G.  aSingular points of smooth mappingsb  aLondonbPitmanc1979  a239p. Index. Appendix  aResearch notes in Mathematicsv v.25  a  a