1. V. P. Minenko, ?Limiting enrichment of intermediate isotopes on withdrawal from the ends of the cascade,? At. Energ.,33, No. 2, 703?704 (1972).
2. S. Levin, ?The separation of isotopes of elements other than uranium by the gaseous diffusion processes,? J. Chem. Phys. Phys.-Chem. Biol.,60, No. 1?2, 277?284 (1963).
3. D. Staschewski, ?Numerische Methoden zur Bestimmung der16O-und17O-Anreicherung durch Gegenstromdestillation von Wasser,? Chem.-Ing.-Techn.,40, No. 8, 748?756 (1968).
4. E. V. Levin, N. I. Laguntsov, and G. A. Sulaberidze, ?Method of numerical investigation of nonsteady processes in multisection units for separating multicomponent isotopic mixtures,? Inzh.-Fiz. Zh.,43, No. 3, 456?462 (1982).
5. E. Halle, ?Evaluation of the performance of thermal diffusion column,? J. Chem. Phys. Phys.-Chem. Biol.,60, No. 1?2, 187?194 (1963).