TY  - JOUR
AU  - Philip Hartman
TI  - Uniqueness of Principal Values, Complete Monotonicity of Logarithmic Derivatives of  Principal Solutions, and Oscillation Theorems.
JO  - Mathematische Annalen
PY  - 1979
SP  - 257
EP  - 282
VL  - 241
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MAN_1979__241_163265/
ID  - MAN_1979__241_163265
ER  -