http://bmj.bmjjournals.com/cgi/content/full/330/7503/1297
Marcel G W Dijkgraaf ; Bart P van der Zanden ; Corianne A J M de Borgie ; Peter Blanken ; Jan M van Ree ; Wim van den Brink
"Prescribing methadone plus heroin to chronic, treatment resistant addicts is less costly than methadone alone because it reduces criminal behaviour."