%0 Journal Article
%A Philip Hartman
%T Uniqueness of Principal Values, Complete Monotonicity of Logarithmic Derivatives of  Principal Solutions, and Oscillation Theorems.
%J Mathematische Annalen
%D 1979
%P 257-282
%V 241
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1979__241_163265/
%F MAN_1979__241_163265