Bambach, Richard K.; Bush, Andrew M.; Erwin, Douglas H. (2007). "Autecology and the filling of ecospace: key metazoan radiations". Palæontology. 50 (1): 1–22. doi:10.1111/j.1475-4983.2006.00611.x. S2CID84142740.
Bambach, Richard K.; Bush, Andrew M.; Erwin, Douglas H. (2007). "Autecology and the filling of ecospace: key metazoan radiations". Palæontology. 50 (1): 1–22. doi:10.1111/j.1475-4983.2006.00611.x. S2CID84142740.
Darwin (1859). On the origin of species by natural selection. Murray, London, United Kingdom. pp. 315–31. ISBN1602061440. OCLC176630493. {{cite book}}: ISBN / Date incompatibility (help)