%0 Journal Article
%A Demir N. Kupeli
%T On Conjugate and Focal Points in Semi-Riemannian Geometry.
%J Mathematische Zeitschrift
%D 1988
%P 569-590
%V 198
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZ_1988__198_3_173944/
%F MZ_1988__198_3_173944