Carnevali, G., Cetzal-Ix, W., Tapia-Muñoz, J.L. & Romero-González, G.A. (2015)

The world upside down: the first Kefersteinia (Orchidaceae: Zygopetalinae) with non-resupinate flowers

. Phytotaxa 239 (2): 165–173. https://doi.org/10.11646/phytotaxa.239.2.5