TY  - JOUR
AU  - I.L. Mel'nichuk
TI  - Semigroups with n-closed subsets.
JO  - Semigroup forum
PY  - 1989
SP  - 105
EP  - 108
VL  - 39
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SF_1989__39_2_134979/
LA  - en
ID  - SF_1989__39_2_134979
ER  -