TY  - JOUR
AU  - Vrkoč, Ivo
TI  - The class of functions fulfilling the inequality $\Vert f(x+z)-f(x)-f(y+z)+f(y) \Vert \le \Vert x-y \Vert \omega(\Vert z \Vert)$
JO  - Czechoslovak Mathematical Journal
PY  - 1969
SP  - 500
EP  - 514
VL  - 19
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1969.100917/
DO  - 10.21136/CMJ.1969.100917
LA  - en
ID  - 10_21136_CMJ_1969_100917
ER  -