@article {Manchon:March 2002:0011-4642:1,
	author = "Manchon P.M.G.",
	title = "Hypersurfaces in \Bbb {R}^n and critical points in their external region",
	journal = "Czechoslovak Mathematical Journal",
	volume = "52",
	year = "March 2002",
	abstract = "<P>In this paper we study the hypersurfaces M^n given as connected compact regular fibers of a differentiable map f : \Bbb {R}^{n+1} \rightarrow \Bbb R, in the cases in which f has finitely many nondegenerate critical points in the unbounded component of \Bbb {R}^{n+1} - M^n.</P>",
	pages = "1-9(9)",
	url = "http://www.ingentaconnect.com/content/klu/cmaj/2002/00000052/00000001/00411635"
}