%0 Journal Article
%A N. V. Efimov
%T Surfaces with a~slowly changing negative curvature
%J Trudy Matematicheskogo Instituta imeni V.A. Steklova
%D 1966
%P 1-55
%V 21
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/RM_1966_21_5_a0/
%G en
%F RM_1966_21_5_a0