To cite the ridge package, use:

  Cule E, Moritz S, Frankowski D (2022). _ridge: Ridge Regression with
  Automatic Selection of the Penalty Parameter_. R package version 3.3,
  <https://CRAN.R-project.org/package=ridge>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {ridge: Ridge Regression with Automatic Selection of the Penalty Parameter},
    author = {Erika Cule and Steffen Moritz and Dan Frankowski},
    year = {2022},
    note = {R package version 3.3},
    url = {https://CRAN.R-project.org/package=ridge},
  }