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3. H.W. Watson and F. Galton, On the Probability of the Extinction of Families, J.R. Anthropol. Inst. G.B. Irel. 4, 138–144 (1875).
4. H.P. Hsu, Schaums’s outline, probability, random variables, and random processes, 3rd ed. (McGraw-Hill Education, 2014).
5. B. Krishna Kumar, Stochastic Modelling in Physical and Biological Sciences, (Narosa Publishing House, 2015).