1. Fisher RA. Statistical Methods for Research Workers. Edinburgh United Kingdom: Oliver & Boyd; 1925.
2. Kleinbaum DG Kupper LL Muller KE. Applied Regression Analysis and Other Multivariable Methods. 2nd ed. Boston Mass: PWS-Kent Publishing; 1988.
3. Zar JH. Biostatistical Analysis. Upper Saddle River NJ: Prentice Hall; 1999.
4. Sit V. Analyzing ANOVA Designs: Biometrics Information Handbook No. 5. Province of British Columbia Ministry of Forests Research Program. Working paper 07/1995. Available at: http://www.for.gov.bc.ca/hfd/pubs/docs/Wp/Wp07.pdf. Accessed July 25 2007.
5. National Institute of Standards and Technology Information Technology Library. NIST/SEMATECH e-Handbook of Statistical Methods . Available at: http://www.itl.nist.gov/div898/handbook/prc/section4/prc43.htm. Accessed July 25 2007.