Glossary of Plant Systematics (1st ed.) by Simpson (2006)
- One of several uniseriate (one-cell-thick), filamentous processes that function in anchorage and water/mineral absorption, arising from the gametophytes of free-living gametophytes and from the underground, sporophytic stems of some ferns (e.g. the psilophytes).
Glossary of "Life (9th ed.)" by Sadava et al. (2011)
- Hairlike extensions of cells in mosses, liverworts, and a few vascular plants that serve the same function as roots and root hairs in vascular plants. The term is also applied to branched, rootlike extensions of some fungi and algae.
- 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.