References
- Mainland D. Elementary medical statistics. W. B. Saunders Co., Philadelphia 1963; 306
- McNemar Q. Psychological statistics. J. Wiley and Sons, New York 1969; 180
- Mills F. C. Statistical methods applied to economics and business. H. Holt and Co., New York 1938; 157
- Spiegel M. R. Theory and problems of statistics. Schaum Publishing Co., New York 1961; 73