@article{barbosa_costa_arruda_1981,  title={New field observations on the competitive displacement between two species of planorbid snails inhabiting Northeastern Brasil},  volume={76},  ISSN={0074-0276},  url={https://doi.org/10.1590/S0074-02761981000400004},  DOI={10.1590/S0074-02761981000400004},  number={4},  journal={Memórias do Instituto Oswaldo Cruz},  publisher={Instituto Oswaldo Cruz, Ministério da Saúde},  author={Barbosa, F. S. and Costa, D. P. Pereira da and Arruda, F.},  year={1981},  month={Oct},  pages={361–366} }