1. Stein, W. D., Movement of Molecules Across Cell Membranes (Academic Press, New York, 1967).
2. Cussler, E. L., Evans, D. F., and Matesich, M. A., Science, 172, 377 (1971).
3. Choy, E. M., Evans, D. F., and Cussler, E. L., J. Am. chem. Soc. (in the press).
4. Li, N. N., A.I.Ch.E.Jl, 17, 459 (1971); Ind. Eng. Chem., Process Des. Dev., 10, 215 (1971).
5. Li, N. N., and Shrier, A. L., in Recent Advances in Separation Science (edit. by Li, N. N., CRC Press, Cleveland, 1972).