To cite package ‘OPI’ in publications use:

Turpin A (2026). OPI: Open Perimetry Interface. R package version 3.1.0, https://CRAN.R-project.org/package=OPI.

Corresponding BibTeX entry:

  @Manual{,
    title = {OPI: Open Perimetry Interface},
    author = {Andrew Turpin},
    year = {2026},
    note = {R package version 3.1.0},
    url = {https://CRAN.R-project.org/package=OPI},
  }