2021-01-26 gaff-2.11.dat Wang, J., Wolf, R.M., Caldwell, J.W., Kollman, P.A., and Case, D.A. (2004). Development and testing of a general amber force field. J. Comput. Chem. 25, 1157-1174. Wang, J., Wang, W., Kollman P. A.; Case, D. A. Automatic atom type and bond type perception in molecular mechanical calculations. Journal of Molecular Graphics and Modelling , 25, 2006, 247260.