Cheng Zhiliang, Thorek Daniel L J, Tsourkas Andrew
Department of Bioengineering, University of Pennsylvania, 210 South 33rd Street, 240 Skirkanich Hall, Philadelphia, PA 19104, USA.
Angew Chem Int Ed Engl. 2010;49(2):346-50. doi: 10.1002/anie.200905133.