Merrill, Ray M. Introduction to epidemiology. - 6th ed. / Ray M. Merrill. - Sudbury, Mass. : Jones and Bartlett Publishers, c2013 - xi, 417 p. : ISBN: 9781449665487 (pbk.) Subjects--Topical Terms: Epidemiology.Epidemiologic Methods.Epidemiology. National Library of Medicine Call No.: WA 950