Clinical epidemiology :
Fletcher, Robert H.
Clinical epidemiology : the essentials / Robert H. Fletcher, Suzanne W. Fletcher. - 4th ed. - Philadelphia : Lippincott Williams & Wilkins, c2005. - xv, 252 p. : col. ill., col. map ; 26 cm.
Clinical epidemiology : the essentials / Robert H. Fletcher, Suzanne W. Fletcher. - 4th ed. - Philadelphia : Lippincott Williams & Wilkins, c2005. - xv, 252 p. : col. ill., col. map ; 26 cm.