L.E.Skog & L.P.Kvist (Fritsch) 2000 - Skog LE, Kvist LP (2000) Revision of Gasteranthus (Gesneriaceae). Systematic Botany Monographs 59: 1-118. doi: 10.2307/25027883.
There is no corrections for Gasteranthus calcaratus subsp. calceolus yet.