Stanley Zammit, Peter Allebeck, Sven Andreasson, Ingvar Lundberg, Glyn Lewis
Zammit S, Allebeck P, Andreasson S, Lundberg I, Lewis G.
Self reported cannabis use as a risk factor for schizophrenia in Swedish conscripts of 1969: historical cohort study
BMJ 2002; 325 :1199
doi:10.1136/bmj.325.7374.1199