J.C.Manning & Goldblatt 2004 - Goldblatt P, Manning JC (2004) New Species of Ixia (Crocoideae) and Moraea (Iridoideae), and Taxonomic Notes on Some Other African Iridaceae. Novon 14(3): 288-298. Retrieved from http://www.jstor.org/stable/3393286
There is no corrections for Ixia superba yet.