Farci P, Novick D M, Lai M E, Orgiana G, Strazzera A, Beatrice S T, Des Jarlais D C, Balestrieri A
Department of Internal Medicine, University of Cagliari, Via San Giorgio, Italy.
Am J Epidemiol. 1988 Jun;127(6):1312-4. doi: 10.1093/oxfordjournals.aje.a114924.