%0 Journal Article
%A Gerd Ronning
%T On the Nonnegativity of XX* and its Relevance in Econometrics.
%J Metrika
%D 1985
%P 35-47
%V 32
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MET_1985__32_175984/
%F MET_1985__32_175984