Authors: A J Hartz; H Krakauer; E M Kuhn; M Young; S J Jacobsen; G Gay; L Muenz; M Katzoff; R C Bailey; A A Rimm Journal: N Engl J Med Date: 1989-12-21 Impact factor: 91.245
Authors: A L Stewart; S Greenfield; R D Hays; K Wells; W H Rogers; S D Berry; E A McGlynn; J E Ware Journal: JAMA Date: 1989-08-18 Impact factor: 56.272