@article{pires_guerra-sommer_2004,  title={Sommerxylon spiralosus from Upper Triassic in southernmost Paraná Basin (Brazil): a new taxon with taxacean affinity},  volume={76},  ISSN={0001-3765},  url={https://doi.org/10.1590/S0001-37652004000300013},  DOI={10.1590/S0001-37652004000300013},  number={3},  journal={Anais da Academia Brasileira de Ciências},  publisher={Academia Brasileira de Ciências},  author={Pires, Etiene F. and Guerra-Sommer, Margot},  year={2004},  month={Sep},  pages={595–609} }