TY  - JOUR
A1  - Ridder, G.
A1  - Woutersen, T.M.
T1  - The Singularity of the Information Matrix of the Mixed Proportional Hazard Model
Y1  - 2003
DO  - 10.1111/1468-0262.00460
JF  - Econometrica
VL  - 71
IS  - 5
SP  - 1579
EP  - -1589

ER  -