GrzegorzG.NiedźwiedzkiGrzegorzG. i inni, Tetrapod trackways from the early Middle Devonian period of Poland, „Nature”, 463 (7277), 2010, s. 43-48, DOI: 10.1038/nature08623, PMID: 20054388.
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GrzegorzG.NiedźwiedzkiGrzegorzG. i inni, Tetrapod trackways from the early Middle Devonian period of Poland, „Nature”, 463 (7277), 2010, s. 43-48, DOI: 10.1038/nature08623, PMID: 20054388.