^García-Bellido, Diego C., John R. Paterson, and Gregory D. Edgecombe. (2013). “Cambrian palaeoscolecids (Cycloneuralia) from Gondwana and reappraisal of species assigned to Palaeoscolex”. Gondwana Research24 (2): 780-795. doi:10.1016/j.gr.2012.12.002.