1. N. ARLEY and K. R. BUCH, Introduction to the Theory of Probability and Statistics. New York, 1950.
2. S. N. BERNSHTEIN, Teoriya veroyatnostei (Theory of Probability). Gostekhizdat, 1946, 556 pp.
3. G. P. BOYEV, Teoriya veroyatnostei (Theory of Probability). Gostekhizdat, 1950, 368 pp.
4. N. A. BORODACHEV, Analiz kachestva i tochnosti proizvodstva (Analysis of the Quality and Precision of Production). Mashgiz, 1946, 249 pp.
5. K. A. BROWNLEE, Statistical Investigations in Industry.