Zkamenělé otisky stop neznámého ediakarského tvora, foto Zhe Chen et al., Late Ediacaran trackways produced by bilaterian animals with paired appendages, Science Advances 06 Jun 2018:, Vol. 4, no. 6, eaao6691, DOI: 10.1126/sciadv.aao6691, CC BY-NC 4.0, https://creativecommons.org/licenses/by-nc/4.0/.