%0 Journal Article %A J. J. Charatonik %T The set function T and homotopies %J Colloquium Mathematicum %D 1978 %P 271-274 %V 39 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-39-2-271-274/ %R 10.4064/cm-39-2-271-274 %G en %F 10_4064_cm_39_2_271_274