title: [Development of medical costs in a medical network and similar groups after an intervention from quality circles].
authors: BKK Opel, jetzt BKK Aktiv, Rüsselsheim. heike.papendick@bkkaktiv.de
authors: Heike
authors: H
authors: Papendick
authors: Joachim
authors: J
authors: Fessler
authors: Joseph
authors: J
authors: Gross