To cite package ‘possum’ in publications use:

  Longros C, Chourio Barboza D (2026). _possum: Surgical Risk
  Prediction with the POSSUM Score Family_. R package version 0.1.0,
  <https://github.com/chrislongros/possum>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {possum: Surgical Risk Prediction with the POSSUM Score Family},
    author = {Christos Longros and Daniel Enrique {Chourio Barboza}},
    year = {2026},
    note = {R package version 0.1.0},
    url = {https://github.com/chrislongros/possum},
  }