R. M. K.  Saunders and Fowler, K., ?The supraspecific taxonomy and evolution of the fern genusAzolla (Azollaceae)?, Plant Systematics and Evolution, vol. 184, 1993.

J. S.  Metzgar, Schneider, H., and Pryer, K. M., ?Phylogeny and divergence time estimates for the fern genus Azolla (Salviniaceae)?, International Journal of Plant Sciences, no. 168, 2007.

E. M.  Bennet, Flora of the Perth Region. 1994.

R. J.  Chinnock, Flora of Australia - Family Azollaceae. 1994.