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2. R.v. Mises: “On the Classification of Observation Data in the Distinct Groups,” Annals of Mathematical Statistics, 1945, vol. 16 No. 1.
3. R. v. Mises: “Vorlesungen aus dem Gebiete der Angewandte Mathematik. I. Band. Wahrscheinlichkeitsrechnung,” F. Deuticke, Leipzig und Wien, 1931.
4. Katsuhiko Nishimura, Chikio Hayashi: “Parole Prediction,” Research Series I, The Central Training Institute of Correction and Rehabilitation Personnel, 1949.
5. Chikio Hayashi: “On the Quantification of Qualitative Data from the Mathematico-Statistical Point of View,” Research Series II, the Central Training Institute of Correction and Rehabilitation Personnel, 1950.