Glossary of "Plant Systematics (1st ed.)" by Simpson (2006)
- The formation of new species from preexisting species.
Glossary of "Life (9th ed.)" by Sadava et al. (2011)
- The process of splitting one population into two populations that are reproductively isolated from one another.
Glossary of "The Evolution of Plants (2nd ed.)" by Willis & McElwain (2014)
- The formation of a new species.
Glossary of "Ancestors in Our Genome" by Harris (2015)
- the process whereby one species splits to form two or more reproductively isolated species.
- Harris, E. E. 2015. Ancestors in Our Genome: the New Science of Human Evolution. - xx + 226 pp. Oxford University Press, New York.
- Simpson, M. G. 2006. Plant Systematics. -xi + 590 pp. Elsevier Academic Press, Oxford.
- Sadava, D., Hillis, D. M., Heller, H. C. & Berenbaum, M. R. 2011. Life: The Science of Biology, 9th ed. -xliv + 1266 pp. Sinauer Associates, Inc., Sunderland.
- Willis, K. J. & McElwain, J. C. 2014. The Evolution of Plants, 2nd ed. -ix + 398 pp. Oxford University Press, Oxford.