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Clack, J. - http://www.zoo.cam.ac.uk/zoostaff/clack.htm
Early tetrapod evolution (Univ. Cambridge, Mus. of Zoology). |
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Laurin, M. - http://tolweb.org/tree/laurin/Laurin_Home_page.html
The origin and phylogeny of tetrapods (Université Paris). |
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Bolt, John R. - http://fm1.fieldmuseum.org/aa/staff_page.cgi?staff=bolt
Early diversification of tetrapods, particularly amphibians(Field Museum of Natural History). |