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Smits, Frans TH. M., Karin A. Wittkampf, Aart H. Schene, Patrick J.E Bindels, och Henk C.P.M van Weert. Interventions On Frequent Attenders in Primary Care: A Systematic Literature Review. Informa Healthcare, 2008.

Smits, Frans TH. M., et al. Interventions On Frequent Attenders in Primary Care: A Systematic Literature Review. Informa Healthcare, 2008.