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2. Dallas, A. C. (1975). These papers were not available to the author at the time of writing this paper (c.f. Galambos-Kotz [3]). On a characterization by conditional variance,Manuscript, Athens University, Greece.
3. Galambos, J. and Kotz, S. (1978).Characterizations of Probability Distributions, Lecture Notes in Mathematics 675, Springer-Verlag.
4. Huang, J. S. (1978). On a “lack of memory” property,University of Guelph Statistical Series, 1978–84.
5. Klebanov, L. B. (1977). Some results related to characterization of the exponential distributions, Pre-print in Russian, to appear inTheory Prob. its Appl.