To cite package ‘soilKey’ in publications use:

  Rodrigues, H. (2026). soilKey: Automated soil profile classification
  per WRB 2022, SiBCS 5, and USDA Soil Taxonomy 13. R package version
  0.9.97. https://github.com/HugoMachadoRodrigues/soilKey

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {soilKey: Automated soil profile classification per WRB 2022, SiBCS 5, and USDA Soil Taxonomy 13},
    author = {Hugo Rodrigues},
    year = {2026},
    note = {R package version 0.9.97},
    doi = {10.5281/zenodo.19930112},
    url = {https://github.com/HugoMachadoRodrigues/soilKey},
  }

  Vaz, G. J., Silva Neto, L. de F. da, & Barbedo, J. G. A. (2025).
  SmartSolos Expert: an expert system for Brazilian soil
  classification. Smart Agricultural Technology, 10, 100735.
  doi:10.1016/j.atech.2024.100735

A BibTeX entry for LaTeX users is

  @Article{,
    title = {SmartSolos Expert: an expert system for Brazilian soil classification},
    author = {Glauber {J. Vaz} and L. de F. da {Silva Neto} and Jayme {G. A. Barbedo}},
    journal = {Smart Agricultural Technology},
    year = {2025},
    volume = {10},
    pages = {100735},
    doi = {10.1016/j.atech.2024.100735},
    url = {https://www.agroapi.cnptia.embrapa.br/store/apis/info?name=SmartSolosExpert&version=v1&provider=agroapi},
  }

  Vaz, G. J., Silva Neto, L. de F. da, Lima, R. N., & Oliveira, S. R.
  de M. (2019). Uma API para a classificacao de solos do Brasil. In: 12
  Congresso Brasileiro de Agroinformatica, Indaiatuba. Anais, p. 63-72.
  SBIAGRO, Ponta Grossa.

A BibTeX entry for LaTeX users is

  @InProceedings{,
    title = {Uma API para a classificacao de solos do Brasil},
    author = {Glauber {J. Vaz} and L. de F. da {Silva Neto} and R. N. Lima and S. R. de M. Oliveira},
    booktitle = {Anais do 12 Congresso Brasileiro de Agroinformatica (SBIAGRO 2019)},
    year = {2019},
    pages = {63--72},
    address = {Indaiatuba, SP, Brazil},
    publisher = {SBIAGRO},
  }

  Vaz, G. J., Silva Jr, A. F., & Silva Neto, L. de F. da (2023).
  Brazilian soil data for taxonomic classification. Redape, V1.
  doi:10.48432/PYKKA7

A BibTeX entry for LaTeX users is

  @Misc{,
    title = {Brazilian soil data for taxonomic classification},
    author = {Glauber {J. Vaz} and A. F. {Silva Jr} and L. de F. da {Silva Neto}},
    year = {2023},
    doi = {10.48432/PYKKA7},
    note = {Redape (Embrapa Research Data Repository), V1},
  }

  Leenaars, J. G. B., van Oostrum, A. J. M., & Ruiperez Gonzalez, M.
  (2014). Africa Soil Profiles Database, Version 1.2. ISRIC Report
  2014/01. ISRIC -- World Soil Information, Wageningen.

A BibTeX entry for LaTeX users is

  @TechReport{,
    title = {Africa Soil Profiles Database, Version 1.2},
    author = {J. G. B. Leenaars and A. J. M. {van Oostrum} and M. {Ruiperez Gonzalez}},
    institution = {ISRIC -- World Soil Information},
    address = {Wageningen, NL},
    number = {ISRIC Report 2014/01},
    year = {2014},
    url = {https://isric.org/projects/africa-soil-profiles-database-afsp},
  }

  Fernandez-Ugalde, O., Scarpa, S., Orgiazzi, A., Panagos, P., Van
  Liedekerke, M., Marechal, A., & Jones, A. (2022). LUCAS 2018 SOIL
  Component: sampling intensity, harmonisation and procedures for the
  collection of soil samples. JRC Technical Report 130218.
  doi:10.2760/215013

A BibTeX entry for LaTeX users is

  @TechReport{,
    title = {LUCAS 2018 SOIL Component: sampling intensity, harmonisation and procedures for the collection of soil samples},
    author = {O. Fernandez-Ugalde and S. Scarpa and A. Orgiazzi and P. Panagos and M. {Van Liedekerke} and A. Marechal and A. Jones},
    institution = {European Commission, Joint Research Centre},
    address = {Ispra, IT},
    number = {JRC Technical Report 130218},
    year = {2022},
    doi = {10.2760/215013},
  }

  Orgiazzi, A., Ballabio, C., Panagos, P., Jones, A., &
  Fernandez-Ugalde, O. (2018). LUCAS Soil, the largest expandable soil
  dataset for Europe: a review. European Journal of Soil Science,
  69(1), 140-153. doi:10.1111/ejss.12499

A BibTeX entry for LaTeX users is

  @Article{,
    title = {LUCAS Soil, the largest expandable soil dataset for Europe: a review},
    author = {A. Orgiazzi and C. Ballabio and P. Panagos and A. Jones and O. Fernandez-Ugalde},
    journal = {European Journal of Soil Science},
    year = {2018},
    volume = {69},
    number = {1},
    pages = {140--153},
    doi = {10.1111/ejss.12499},
  }