Friedman HS, Pegg AE, Johnson SP, Loktionova NA, Dolan ME, Modrich P, Moschel RC, Struck R, Brent TP, Ludeman S, Bullock N, Kilborn C, Keir S, Dong Q, Bigner DD, Colvin OM. Modulation of cyclophosphamide activity by O6-alkylguanine-DNA alkyltransferase. Cancer Chemother Pharmacol. 1999; 43(1):80-5.