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Gibert, J. M. de; Domènech, R.; Martinell, J. (2004). "An ethological framework for animal bioerosion trace fossils upon mineral substrates with proposal of new class, fixichnia". Lethaia. 37 (4): 429–437. Bibcode:2004Letha..37..429G. doi:10.1080/00241160410002144.