1. C. B. Magee, M. J. Pool, W. D. McMullen, R. C. Jerner, and D. G. Ellis, ?Investigation of the Characteristics of intermetallic compounds as thermionic emitters.? Technical Summary Report to the Office of Naval Research under Contract NONR-3361(01), University of Denver, Denver, Colo. DRI-2079 (December 31, 1962).
2. C. G. Magee, M. J. Pool, W. D. McMullen, R. C. Jerner, and R. H. Cox, ?Investigation of the Characteristics of Intermetallic Compounds as Thermionic Emitters,? Final Technical Summary Report to the Office of Naval Research under Contract NONR-3361(01), University of Denver, Denver, Colo., DRI-2137 (December 31, 1963).
3. C. Herring and M. H. Nichols,Rev. Mod. Phys. 21, 185 (1949).
4. M. H. Nichols,Phys. Rev. 78, 158 (1960).
5. M. H. Nichols,Phys. Rev. 57, 297 (1940).