TY  - JOUR
AU  - Svoboda, Karel
TI  - On characterization of the sphere in $E^4$ by means of the parallelness of certain vector fields
JO  - Časopis pro pěstování matematiky
PY  - 1980
SP  - 56
EP  - 72
VL  - 105
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.21136/CPM.1980.118047/
DO  - 10.21136/CPM.1980.118047
LA  - en
ID  - 10_21136_CPM_1980_118047
ER  -