TY  - JOUR
AU  - R. Dacić
TI  - The cosine functional equation for groups
JO  - Matematički vesnik
PY  - 1969
SP  - 339 
VL  - 21
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MV_1969_21_3_a12/
ID  - MV_1969_21_3_a12
ER  -