TY  - JOUR
AU  - R. I. Grigorchuk
TI  - Superamenability and the problem of occurrence of free semigroups
JO  - Funkcionalʹnyj analiz i ego priloženiâ
PY  - 1987
SP  - 74
EP  - 75
VL  - 21
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/FAA_1987_21_1_a10/
LA  - ru
ID  - FAA_1987_21_1_a10
ER  -