TY  - BOOK
AU  - Fletcher,Robert H.
AU  - Fletcher,Suzanne W.
AU  - Wagner,Edward H.
TI  - Clinical epidemiology: the essentials 
SN  - 0683032690
PY  - 1996///
CY  - Baltimore
PB  - Williams & Wilkins
KW  - Epodemiologic methods
N1  - Includes bibliographical references and index
ER  -