APA Format
Sackett, David L.
; Haynes, R. Brian; Guyatt, Gordon H.
. (1985;1991). Clinical epidemiology : a basic science for clinical medicine. Boston : Little, Brown
MLA Format
Sackett, David L.; Haynes, R. Brian; Guyatt, Gordon H.
. Clinical epidemiology : a basic science for clinical medicine. Boston : Little, Brown, 1985;1991
Australian/Harvard Format
Sackett, David L.
; Haynes, R. Brian; Guyatt, Gordon H.
. 1985;1991. Clinical epidemiology : a basic science for clinical medicine. Little, Brown, Boston
Warning: These citations may not always be 100% accurate.