To cite package ‘GetoptLong’ in publications use:

Gu Z (2026). GetoptLong: Parsing Command-Line Arguments and Simple Variable Interpolation. R package version 1.1.0, https://github.com/jokergoo/getoptlong.

Corresponding BibTeX entry:

  @Manual{,
    title = {GetoptLong: Parsing Command-Line Arguments and Simple
      Variable Interpolation},
    author = {Zuguang Gu},
    year = {2026},
    note = {R package version 1.1.0},
    url = {https://github.com/jokergoo/getoptlong},
  }