%0 Journal Article
%A Svoboda, Karel
%T On characterization of the sphere in $E^4$ by means of the parallelness of certain vector fields
%J Časopis pro pěstování matematiky
%D 1980
%P 56-72
%V 105
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.21136/CPM.1980.118047/
%R 10.21136/CPM.1980.118047
%G en
%F 10_21136_CPM_1980_118047