@article{paraense_1990,  title={Biomphalaria obstructa (Morelet, 1849): a study of topotypic specimens (Mollusca: pulmonata: planorbidae)},  volume={85},  ISSN={0074-0276},  url={https://doi.org/10.1590/S0074-02761990000400002},  DOI={10.1590/S0074-02761990000400002},  number={4},  journal={Memórias do Instituto Oswaldo Cruz},  publisher={Instituto Oswaldo Cruz, Ministério da Saúde},  author={Paraense, W. Lobato},  year={1990},  month={Oct},  pages={391–399} }