TY  - JOUR
A1  - Hess, K.R.
T1  - Graphical methods for assessing violations of the proportional hazards assumption in Cox regression
Y1  - 1995
DO  - 10.1002/sim.4780141510
JF  - Statistics in Medicine
VL  - 14
IS  - 15
SP  - 1707
EP  - -1723

ER  -