9Kalish ML, Baldwin A, Raktham S, et al. The evolving molecular epidemiology of HIV-1 envelope subtypes in IDU in Bangkok,Thailand; implications for HIV vaccine trials. AIDS, 1995, 9: 851-854.
10Nemkar YR. HIV type I subtype E in commercial sex worker and IDU in southern Vietnam. AIDS Res Hum Retroviruses, 1996,9 : 841-846