To cite package ‘backports’ in publications use:

  Lang M, Murdoch D, R Core Team (2024). _backports: Reimplementations
  of Functions Introduced Since R-3.0.0_. R package version 1.5.0,
  <https://github.com/r-lib/backports>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {backports: Reimplementations of Functions Introduced Since R-3.0.0},
    author = {Michel Lang and Duncan Murdoch and {R Core Team}},
    year = {2024},
    note = {R package version 1.5.0},
    url = {https://github.com/r-lib/backports},
  }