To cite package ‘landform’ in publications use:

Alberti G (2023). landform: Topographic Position Index-Based Landform Classification. R package version 0.2, https://CRAN.R-project.org/package=landform.

Corresponding BibTeX entry:

  @Manual{,
    title = {landform: Topographic Position Index-Based Landform
      Classification},
    author = {Gianmarco Alberti},
    year = {2023},
    note = {R package version 0.2},
    url = {https://CRAN.R-project.org/package=landform},
  }