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Twitchett, R.J. (2007). "The Lilliput effect in the aftermath of the end-Permian extinction event". Palaeogeography, Palaeoclimatology, Palaeoecology. 252 (1–2): 132–144. Bibcode:2007PPP...252..132T. doi:10.1016/j.palaeo.2006.11.038.