S. B.  Hoot, Napier, N. S., and Taylor, W. C., ?Revealing unknown or extinct lineages within Isoëtes (Isoëtaceae) using DNA sequences from hybrids?, American Journal of Botany, vol. 91, no. 6, pp. 899 - 904, 2004.

E.  Schuettpelz and Hoot, S. B., ?Inferring the root of Isoëtes: Exploring alternatives in the absence of an acceptable outgroup?, Systematic Botany, vol. 31, no. 2, pp. 258 - 270, 2006.