Glossary of "Plant Biology (1st ed.)" by Graham et al. (2003)
- The structure ontained within the ovary that gives rise to the female gametophyte and, when fertilized and mature, a seed.
Glossary of Plant Systematics (1st ed.) by Simpson (2006)
- An immature seed, prior to fertilization; a megasporangium enveloped by one or more integuments. (plant part, gynoecium part)
Glossary of "Life (9th ed.)" by Sadava et al. (2011)
- In plants, a structure comprising the megasporangium and the integument, which develops into a seed after fertilization.
Glossary of "The Evolution of Plants (2nd ed.)" by Willis & McElwain (2014)
- Unfertilized seed.
- Graham, L. E., Graham, J. M. & Wilcox, L. W. 2003. Plant Biology. -xxxv + 497 pp. Pearson Education, Inc., Upper Saddle River.
- 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.