%0 Journal Article
%A Anna Zofia Krygowska
%T CIEAEM 39
%J Didactica Mathematicae
%D 1989
%P  149-160
%V 10
%N 01
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.14708/dm.v10i01.6870/
%R 10.14708/dm.v10i01.6870
%G pl
%F 10_14708_dm_v10i01_6870