To cite the penalized package in publications use:

Jelle J. Goeman (2010) L1 penalized estimation in the Cox proportional hazards model, Biometrical Journal, 52 (1) 80-84.

Jelle J. Goeman (2025). Penalized R package, version 0.9-53.

Corresponding BibTeX entries:

  @Article{,
    title = {L1 penalized estimation in the Cox proportional hazards
      model},
    author = {Jelle Goeman},
    journal = {Biometrical Journal},
    number = {52},
    issue = {1},
    pages = {-14},
    year = {2010},
  }

  @Manual{,
    title = {Penalized: L1 (lasso and fused lasso) and L2 (ridge)
      penalized estimation in GLMs and in the Cox model},
    author = {Jelle Goeman and Rosa Meijer and Nimisha Chaturvedi and
      Matthew Lueder},
    year = {2025},
    note = {R package version 0.9-53},
  }