Single-dose tenofovir and emtricitabine for reduction of viral resistance to non-nucleoside reverse transcriptase inhibitor drugs in women given intrapartum nevirapine for perinatal HIV prevention: an open-label randomised trial. - Chi BH; Sinkala M; Mbewe F; Cantrell RA; Kruse G; Chintu N; Aldrovandi GM; Stringer EM; Kankasa C; Safrit JT; Stringer JS (Lancet, 2007)