Polybranchiaspids

@incollection{robertson1957agnatha,
    author = "Robertson, George M.",
    title = "Agnatha",
    year = "1957",
    booktitle = "Geological Society of America Memoirs",
    url = "https://doi.org/10.1130/mem67v2-p995",
    doi = "10.1130/mem67v2-p995",
    pages = "995-998"
}

@incollection{parker1962superclass,
    author = "Parker, T. Jeffery and Haswell, William A.",
    title = "Super-Class Agnatha",
    year = "1962",
    booktitle = "Textbook of Zoology Vertebrates",
    url = "https://doi.org/10.1007/978-1-349-00198-9\_7",
    doi = "10.1007/978-1-349-00198-9\_7",
    pages = "164-202"
}

@article{halsteadtarlo1965a,
    author = "HALSTEAD TARLO, L. B. and WHITING, H. P.",
    title = "A New Interpretation of the Internal Anatomy of the Heterostraci (Agnatha)",
    year = "1965",
    journal = "Nature",
    url = "https://doi.org/10.1038/206148a0",
    doi = "10.1038/206148a0",
    number = "4980",
    pages = "148-150",
    volume = "206"
}

@article{halstead1979internal,
    author = "Halstead, L. B.",
    title = "Internal anatomy of the polybranchiaspids (Agnatha, Galeaspida)",
    year = "1979",
    journal = "Nature",
    url = "https://doi.org/10.1038/282833a0",
    doi = "10.1038/282833a0",
    number = "5741",
    pages = "833-836",
    volume = "282"
}

@misc{halstead1979internal1,
    author = "Halstead, L. B",
    title = "Internal anatomy of the polybranchiaspids (Agnatha, Galeaspida)",
    year = "1979",
    howpublished = "Nature, v. 282, p. 833-836",
    note = "talkorigins\_source = {true}; raw\_reference = {Halstead, L. B., 1979, Internal anatomy of the polybranchiaspids (Agnatha, Galeaspida): Nature, v. 282, p. 833-836.}"
}

Some new impressions have been observed on the visceral surface of a dorsal shield of Ctenaspis sp. from the Lower Devonian of Spitsbergen. They indicate the probable position of the ophthalmicus profundus and o. lateralis nerves, and of two branchial nerves. The impressions left by the branchial arches are also visible on the same specimen. Furthermore, a median dorsal series of circular impressions previously observed in Seretaspis zychi StensiÖ is compared to similar impressions observed in two osteostracans, and it is suggested that vertebral elements were present in the Heterostraci. Finally, the affinities of the Heterostraci are discussed and it is suggested that they may represent the sister group of the Myopterygii (Cephalaspidomorphi + Gnathostomata).

@article{janvier1979new,
    author = "JANVIER, PHILIPPE and BLIECK, ALAIN",
    title = "New Data on the Internal Anatomy of the Heterostraci (Agnatha), with General Remarks on the Phytogeny of the Craniota",
    year = "1979",
    journal = "Zoologica Scripta",
    abstract = "Some new impressions have been observed on the visceral surface of a dorsal shield of Ctenaspis sp. from the Lower Devonian of Spitsbergen. They indicate the probable position of the ophthalmicus profundus and o. lateralis nerves, and of two branchial nerves. The impressions left by the branchial arches are also visible on the same specimen. Furthermore, a median dorsal series of circular impressions previously observed in Seretaspis zychi StensiÖ is compared to similar impressions observed in two osteostracans, and it is suggested that vertebral elements were present in the Heterostraci. Finally, the affinities of the Heterostraci are discussed and it is suggested that they may represent the sister group of the Myopterygii (Cephalaspidomorphi + Gnathostomata).",
    url = "https://doi.org/10.1111/j.1463-6409.1979.tb00640.x",
    doi = "10.1111/j.1463-6409.1979.tb00640.x",
    number = "1-4",
    pages = "287-296",
    volume = "8"
}

@incollection{hentschel1987agnatha,
    author = "Hentschel, Hartmut and Elger, Marlies",
    title = "Agnatha",
    year = "1987",
    booktitle = "Advances in Anatomy Embryology and Cell Biology",
    url = "https://doi.org/10.1007/978-3-642-72866-2\_3",
    doi = "10.1007/978-3-642-72866-2\_3",
    pages = "10-22"
}

@incollection{rieger2010agnatha,
    author = "Rieger, Gunde and Maier, Wolfgang",
    title = "„Agnatha“, Kieferlose",
    year = "2010",
    booktitle = "Spezielle Zoologie",
    url = "https://doi.org/10.1007/978-3-8274-2220-0\_14",
    doi = "10.1007/978-3-8274-2220-0\_14",
    pages = "189-191"
}

@article{gai2018new,
    author = "Gai, Zhikun and Lu, Liwu and Zhao, Wenjin and Zhu, Min",
    title = "New polybranchiaspiform fishes (Agnatha: Galeaspida) from the Middle Palaeozoic of China and their ecomorphological implications",
    year = "2018",
    journal = "PLOS ONE",
    url = "https://doi.org/10.1371/journal.pone.0202217",
    doi = "10.1371/journal.pone.0202217",
    number = "9",
    pages = "e0202217",
    volume = "13"
}

@misc{crossrefNoneagnatha,
    title = "Agnatha",
    year = "None",
    booktitle = "SpringerReference",
    url = "https://doi.org/10.1007/springerreference\_43438",
    doi = "10.1007/springerreference\_43438"
}

@incollection{denisonNoneagnatha,
    author = "Denison, Robert H.",
    title = "Agnatha",
    year = "None",
    booktitle = "Encyclopedia of Earth Science",
    url = "https://doi.org/10.1007/3-540-31078-9\_3",
    doi = "10.1007/3-540-31078-9\_3",
    pages = "10-12"
}