TY  - JOUR
AU  - S. Lajos
TI  - On existence of the identity element in a semigroup
JO  - Matematički vesnik
PY  - 1965
SP  - 155 
VL  - 17
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MV_1965_17_2_a9/
ID  - MV_1965_17_2_a9
ER  -