TY  - JOUR
AU  - M. Kierlańczyk
TI  - On a differential inequality of the type \(X'' + f(t)X \geq 0\)
JO  - Commentationes Mathematicae
PY  - 1979
SP  -  325
EP  - 326
VL  - 21
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.14708/cm.v21i2.5992/
DO  - 10.14708/cm.v21i2.5992
LA  - pl
ID  - 10_14708_cm_v21i2_5992
ER  -