1. W. F. Westendorp, C. M. Bishop, H. Hurwitz, L. M. Coldman and D. J. Ben Daniel, ?Nonthermal ionization in transient heliumcesium discharges,? Phys. Fluids, vol. 4, no. 6, 786?787, 1961.
2. D. J. Ben Daniel and S. Tamor, ?Theory of nonthermal ionization in cesium discharges? Phys. Fluids, vol. 5, no. 4, 500?501, 1962.
3. R. Monti and L. G. Napolitano, ?Influence of excited atoms on the Saha equation for two temperature plasmas,? Paper presented at the XV International Astronautical Congress, Warsaw, September, 1964.
4. A. N. Kraiko and Yu. V. Moskvin, ?Determination of the composition of a two-temperature plasma,? PMTF [Journal of Applied Mechanics and Technical Physics], no. 4, 154?156, 1965.
5. T. Hiramoto, ?Nonequilibrium characteristics of the working plasmas for magnetoplasmadynamic (MPD) generators,? J. Phys. Soc. Japan, vol. 20, no. 6, 1061?1072, 1965.