Dixon, W.J.1981BMPD: Biomedical Data Processing. Berkeley: University of California Press.
2.
Nie, H. ; Hull, C.H.; Jenkins, J.G.; Steinbrenner, K. and D. H. Bent1975SPSS Statistical Package for the Social Sciences. 2nd Edition. New York: McGraw-Hill Book Company.
3.
Waltz, C. and R.B. Bausell1981Nursing Research: Design, Statistics and Computer Analysis. Philadelphia: F.A. Davis Company.