Glossary of "The Cell (5th ed.)" by Alberts et al. (2008)
- Any agent, such as a chemical or a form of radiation, that causes cancer.
Glossary of "Environmental Science: Earth as a Living Planet (2nd ed.)" by Botkin & Keller (1998)
- Any material that is known to produce cancer in humans or other animals.
- Alberts, B., Johnson, A., Lewis, J. Raff, M., Roberts, K. & Walter P. 2008. Molecular Biology of the Cell, 5th ed. -xxxiii + 1268 pp. Garland Science, New York.
- Botkin, D. B. & Keller, E. A. 1998. Environmental Science: Earth as a Living Planet, 2nd ed. -xxxxii + 649 pp. John Wiley & Sons, Inc., New York.