1. Digimorph. Collection of MicroCT images of reptilian skulls: www.digimorph.org.
2. Gans Collections and Charitable fund. Provides access to all volumes of Biology of Reptilia (ed. C Gans): http://carlgans.org/biology-reptilia-online/.
3. Reptile database. Taxonomic and biogeographich information on over 10,000 reptilian species: www.reptile-database.com.
4. The Texan Herper. General information on reptiles: www.thetexanherper.com.
5. University College London Museum. Collection of Amphisbaenia: http://www.ucl.ac.uk/museums-static/obl4he/vertebratediversity/amphisbaenia.html.