Naltrexone for heroin dependence treatment in St. Petersburg, Russia. - Krupitsky EM; Zvartau EE; Masalov DV; Tsoi MV; Burakov AM; Egorova VY; Didenko TY; Romanova TN; Ivanova EB; Bespalov AY; Verbitskaya EV; Neznanov NG; et al. (Journal of substance abuse treatment, 2004)