Monge-Nájera, Julián, and Xianguang Hou. 2000. “Disparity, Decimation and the Cambrian "explosion": Comparison of Eady Cambrian and Present Faunal Communities With Emphasis on Velvet Worms (Onychophora)”. Revista De Biología Tropical 48 (2-3):333–351. https://doi.org/10.15517/rbt.v48i2-3.18718.