TY  - BOOK
AU  - HALL,A.J.
AU  - BARKER,D.J.P.
TI  - PRACTICAL EPIDEMIOLOGY / 
U1  - 614.4 
PY  - 1993///
CY  - [S.N] : 
PB  - ELBS WITH CHURCHILL LIVINGSTONE ، 
KW  - EPIDEMIOLOGY
ER  -