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Delabre, Christiane; etal «Complete Mitochondrial DNA of the Hagfish, Eptatretus burgeri: The Comparative Analysis of Mitochondrial DNA Sequences Strongly Supports the Cyclostome Monophyly». Molecular Phylogenetics and Evolution, 22, 2, 2002, pàg. 184–192. DOI: 10.1006/mpev.2001.1045. PMID: 11820840.
Alysha M. Heimberg, Richard Cowper-Sal·lari, Marie Sémon, Philip C. J. Donoghue, and Kevin J. Peterson, 2010. «microRNAs reveal the interrelationships of hagfish, lampreys, and gnathostomes and the nature of the ancestral vertebrate». PNAS, 107, 45, 09-11-2010, pàg. 19379–19383. DOI: 10.1073/pnas.1010350107. PMC: 2984222. PMID: 20959416.
Delabre, Christiane; etal «Complete Mitochondrial DNA of the Hagfish, Eptatretus burgeri: The Comparative Analysis of Mitochondrial DNA Sequences Strongly Supports the Cyclostome Monophyly». Molecular Phylogenetics and Evolution, 22, 2, 2002, pàg. 184–192. DOI: 10.1006/mpev.2001.1045. PMID: 11820840.
Alysha M. Heimberg, Richard Cowper-Sal·lari, Marie Sémon, Philip C. J. Donoghue, and Kevin J. Peterson, 2010. «microRNAs reveal the interrelationships of hagfish, lampreys, and gnathostomes and the nature of the ancestral vertebrate». PNAS, 107, 45, 09-11-2010, pàg. 19379–19383. DOI: 10.1073/pnas.1010350107. PMC: 2984222. PMID: 20959416.