Forthofer, R. N., Lee, E. S., & Hernandez, M. (2007). Biostatistics: A guide to design, analysis, and discovery (2nd ed.). Elsevier Academic Press.

Forthofer, Ron N., Eun Sul Lee, and Mike Hernandez. Biostatistics: A Guide to Design, Analysis, and Discovery. 2nd ed. Burlington, MA: Elsevier Academic Press, 2007.

Forthofer, Ron N., et al. Biostatistics: A Guide to Design, Analysis, and Discovery. 2nd ed. Elsevier Academic Press, 2007.