%0 Journal Article
%A Joseph Becker
%A J. Denef
%A L. Lipshitz
%T Ultraproducts and Approximation in Local Rings I.
%J Inventiones mathematicae
%D 1979
%P 189-204
%V 51
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM_1979__51_142629/
%F IM_1979__51_142629