To cite package ‘tree’ in publications use:

Ripley B (2025). tree: Classification and Regression Trees. R package version 1.0-45, https://CRAN.R-project.org/package=tree.

Corresponding BibTeX entry:

  @Manual{,
    title = {tree: Classification and Regression Trees},
    author = {Brian Ripley},
    year = {2025},
    note = {R package version 1.0-45},
    url = {https://CRAN.R-project.org/package=tree},
  }