TY  - JOUR
AU  - V. G. Durnev
TI  - Positive theory of a free semigroup
JO  - Doklady Akademii Nauk
PY  - 1973
SP  - 772
EP  - 774
VL  - 211
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1973_211_4_a3/
LA  - ru
ID  - DAN_1973_211_4_a3
ER  -