%0 Journal Article
%A Kratz, Werner
%T Quadratic functionals: positivity, oscillation, Rayleigh's principle
%J Archivum mathematicum
%D 1998
%P 143-151
%V 34
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/ARM_1998__34_1_a13/
%G en
%F ARM_1998__34_1_a13