S. Marks, D. Ciliska, und A. Jull. Evidence-based nursing, 9 (4):
100-4(Oktober 2006)4369<m:linebreak></m:linebreak>LR: 20071115; PUBM: Print; JID: 9815947; ppublish;<m:linebreak></m:linebreak>Critical appraisal.
J. Concato, N. Shah, und R. Horwitz. The New England journal of medicine, 342 (25):
1887-92(Juni 2000)2645<m:linebreak></m:linebreak>Tipus d'estudis.