«Otic Notch». The palaeofiles. University of Bristol. Arkivert fra originalen 27. september 2015. Besøkt 26. september 2015.
doi.org
Smithson, T. R. (januar 1993). «Westlothiana lizziae from the Viséan of East Kirkton, West Lothian, Scotland, and the amniote stem». Earth and Environmental Science Transactions of The Royal Society of Edinburgh. 84 (3-4): 383–412. doi:https://doi.org/10.1017/S0263593300006192Sjekk |doi=-verdien (hjelp).Bruk av |besøksdato= krever at |url= også er angitt. (hjelp)
inist.fr
cat.inist.fr
Smithson & al. (1993): Westlothiana lizziae from the Viséan of East Kirkton, West Lothian, Scotland, and the amniote stem. Transactions of the Royal Society of Edinburgh. Earth sciences no 84: side 383-412. [1]
oxfordjournals.org
sysbio.oxfordjournals.org
Laurin, M. (2004): The Evolution of Body Size, Cope's Rule and the Origin of Amniotes. Systematic Biology no 53 (4): side 594-622. doi: 10.1080/10635150490445706 artikkel
uchicago.edu
pondside.uchicago.edu
Ruta, M.; Coates, M.I. & Quicke, D.L.J. (2003): Early tetrapod relationships revisited. Biological Review no 78: side 251-345.PDFArkivert 22. mai 2008 hos Wayback Machine.
web.archive.org
Ruta, M.; Coates, M.I. & Quicke, D.L.J. (2003): Early tetrapod relationships revisited. Biological Review no 78: side 251-345.PDFArkivert 22. mai 2008 hos Wayback Machine.
«Otic Notch». The palaeofiles. University of Bristol. Arkivert fra originalen 27. september 2015. Besøkt 26. september 2015.