K. M.  Pryer, ?Phylogeny and Evolution of Ferns (Monilophytes) with a focus on the early Leptosporangiate Divergences.?, American Journal of Botany, vol. 91, no. 10, 2004.

E.  Schuettpelz and Pryer, K. M., ?Fern Phylogeny?, Biology and Evolution of Ferns and Lycophytes, 2008.