TY  - JOUR
AU  - D. Strauss
TI  - Semigroup structures on ßN.
JO  - Semigroup forum
PY  - 1992
SP  - 238
EP  - 244
VL  - 44
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SF_1992__44_1_135147/
ID  - SF_1992__44_1_135147
ER  -