@article{reis jr._fontes_neves_santos_1999,  title={Total soil electrical conductivity and critical soil K+ to Ca2+ and Mg2+ ratio for potato crops},  volume={56},  ISSN={0103-9016},  url={https://doi.org/10.1590/S0103-90161999000400030},  DOI={10.1590/S0103-90161999000400030},  number={4},  journal={Scientia Agricola},  publisher={Escola Superior de Agricultura "Luiz de Queiroz"},  author={Reis Jr., Roberto Anjos and Fontes, Paulo Cezar Rezende and Neves, Júlio Cesar Lima and Santos, Nerilson Terra},  year={1999},  month={Oct},  pages={993–997} }