Kaltenbach III, Robert F.; Patel, Mona; Waltermire, Robert E.; Harris, Gregory D.; Stone, Benjamin R. P.; Klabe, Ronald M.; Garber, Sena; Bacheler, Lee T.; Cordova, Beverly C.; Logue, Kelly; Wright, Matthew R.; Erickson-Viitanen, Susan; Trainor, George L. Bioorganic and Medicinal Chemistry Letters, 2003, vol. 13, # 4 p. 605 - 608 doi: 10.1016/S0960-894X(02)01064-8