TY  - JOUR
AU  - Heppes, Aladár
TI  - On the Number of Spheres Which can Hide a Given Sphere
JO  - Canadian journal of mathematics
PY  - 1967
SP  - 413
EP  - 418
VL  - 19
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1967-033-4/
DO  - 10.4153/CJM-1967-033-4
ID  - 10_4153_CJM_1967_033_4
ER  -