U.  Joger, Fritz, U., Guicking, D., Kalyabina-Hauf, S., Nagy, Z. T., Wink, M., Habel, J. C., and Assmann, T., ?Relict populations and endemic clades in Palearctic reptiles: Evolutionary history and implications for conservation?, in Les reptiles du Gabon, Smithsonian Institute, 2010, pp. 149 - 152.

Z. T.  Nagy, Vidal, N., Pauwels, O. S. G., and Weghe, J. P. Vande, ?La super-famille des Caenophidia ? Un aperçu de la systématique des Caenophidia d?Afrique?, in Les reptiles du Gabon, Smithsonian Institute, 2008, pp. 149 - 152.