TY  - JOUR
AU  - Underwood. F.
TI  - Some conditions for the existence of two periodic integrals of the homogeneous linear differential equation of the seoond order
JO  - Mathematische Zeitschrift
PY  - 1933
SP  - 195
EP  - 201
VL  - 36
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZ_1933__36_168396/
ID  - MZ_1933__36_168396
ER  -