Sharina D. Person, Jeroan J. Allison, Catarina I. Kiefe, Michael T. Weaver, O. Dale Williams, Robert M. Centor, Norman W. Weissman,
Nurse staffing and mortality for Medicare patients with acute myocardial infarction. Medical Care. ,vol. 42, pp. 4- 12 ,(2004) ,
10.1097/01.MLR.0000102369.67404.B0