Blain GC, Sobierajski Gd, Martins LL (2023). “The Powersdi: An R-Package for Implementing and Calculating the SPI and Spei Using Data from the Nasa-Power Project.” Social Science Research Network. doi:10.2139/ssrn.4442843, https://www.ssrn.com/abstract=4442843.

Blain GC, Sobierajski GR, Martins LL, Sparks AH (2024). PowerSDI: Calculate Standardised Drought Indices Using NASA POWER Data. R package version 1.0.0, https://github.com/gabrielblain/PowerSDI.

Corresponding BibTeX entries:

  @Article{,
    author = {Gabriel Constantino Blain and Graciela da Rocha
      Sobierajski and Letícia Lopes Martins},
    title = {The Powersdi: An R-Package for Implementing and
      Calculating the SPI and Spei Using Data from the Nasa-Power
      Project},
    journal = {Social Science Research Network},
    year = {2023},
    doi = {10.2139/ssrn.4442843},
    url = {https://www.ssrn.com/abstract=4442843},
  }
  @Manual{,
    title = {{PowerSDI}: Calculate Standardised Drought Indices Using
      NASA POWER Data},
    author = {Gabriel Constantino Blain and Graciela R. Sobierajski and
      Leticia L. Martins and Adam H. Sparks},
    year = {2024},
    note = {R package version 1.0.0},
    url = {https://github.com/gabrielblain/PowerSDI},
  }