17552 Joseph Doob: The development of rigor in mathematical probability (1900-1950).
Am. Math. Monthly 103/7 (1996), 586-595.

M. Kendall/E. Pearson/R. Plackett: Studies in the history of statistics and 
probability. 2 volumes. Griffin 1977.

I. Todhunter: A history of the mathematical theory of probability.
Chelsea 1965 (first edition 1865).