Campbell, N. A., Mitchell, L. G., & Reece, J. B. (1997). Biology: Concepts & connections (2nd ed.). Benjamin Cummings.

Campbell, Neil A., Lawrence G. Mitchell, and Jane B. Reece. Biology: Concepts & Connections. 2nd ed. Menlo Park, Calif.: Benjamin Cummings, 1997.

Campbell, Neil A., et al. Biology: Concepts & Connections. 2nd ed. Benjamin Cummings, 1997.