%0 Journal Article
%T [Lectures presented at Winter school] Section of topology
%J Acta Universitatis Carolinae. Mathematica et Physica
%D 1999
%P 24-25
%V 40
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AUCMP_1999__40_2_a3/
%G en
%F AUCMP_1999__40_2_a3