TY  - JOUR
AU  - Yu. T. Lisitsa
TI  - Hopf’s classification theorem in the theory of shapes
JO  - Doklady Akademii Nauk
PY  - 1975
SP  - 1056
EP  - 1059
VL  - 223
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1975_223_5_a4/
LA  - ru
ID  - DAN_1975_223_5_a4
ER  -