@article {723,
	title = {A Combined Metadynamics and Umbrella Sampling Method for the Calculation of Ion Permeation Free Energy Profiles},
	journal = {J. Chem. Theor. Comp},
	volume = {7},
	year = {2011},
	pages = {2277-2283},
	doi = {10.1021/ct200100e},
	author = {Zhang, Y. and G. A. Voth}
}
