To cite the package:

Pérez-Goya U, Militino AF, Ugarte MD, SanMartin MM- (2019). RGISTools: Tools for downloading and processing time-series of satellite images.

To cite the gap filling method implemented in the function genSmoothingIMA:

Militino AF, Ugarte MD, Pérez-Goya U, Genton MG (2019). “Interpolation of the Mean Anomalies for Cloud-Filling in Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI).” IEEE Transactions on Geoscience and Remote Sensing. http://dx.doi.org/10.1109/TGRS.2019.2904193.

To cite the smoothing method implemented in the function genSmoothingCovIMA:

Militino AF, Ugarte MD, Pérez-Goya U (2011). “Improving the Quality of Satellite Imagery Based on Ground-Truth Data from Rain Gauge Stations.” Remote Sensing, 10(398), 1–16. http://dx.doi.org/10.3390/rs10030398.

Corresponding BibTeX entries:

  @Manual{,
    title = {RGISTools: Tools for downloading and processing
      time-series of satellite images},
    author = {U P{\'e}rez-Goya and A F Militino and M D Ugarte and M
      Montesino - SanMartin},
    year = {2019},
  }
  @Article{,
    title = {Interpolation of the Mean Anomalies for Cloud-Filling in
      Land Surface Temperature (LST) and Normalized Difference
      Vegetation Index (NDVI)},
    author = {A F Militino and M D Ugarte and U P{\'e}rez-Goya and Marc
      G. Genton},
    journal = {IEEE Transactions on Geoscience and Remote Sensing},
    year = {2019},
    url = {http://dx.doi.org/10.1109/TGRS.2019.2904193},
  }
  @Article{,
    title = {Improving the Quality of Satellite Imagery Based on
      Ground-Truth Data from Rain Gauge Stations},
    author = {A F Militino and M D Ugarte and U P{\'e}rez-Goya},
    journal = {Remote Sensing},
    year = {2011},
    volume = {10},
    number = {398},
    pages = {1--16},
    url = {http://dx.doi.org/10.3390/rs10030398},
  }