@book{13206,
	author = {Symposium on Singularities of Smooth Manifolds and Maps, Univ. of Liverpool, Sept. 1969-August 1970 and Wall, C. T. C. ; ed.},
	title = {Liverpool Singularities; proceedings},
	publisher = {Springer-Verlag},
	year = {1971},
	address = {Berlin}
}