TY  - JOUR
A1  - Valderas, J.M.
A1  - Starfield, B.
A1  - Sibbald, B.
A1  - Salisbury, C.
A1  - Roland, M.
T1  - Defining comorbidity: Implications for understanding health and health services
Y1  - 2009
DO  - 10.1370/afm.983
VL  - 7
IS  - 4

ER  -