To cite package ‘afc’ in publications use:

Weigel A (2017). afc: Generalized Discrimination Score. R package version 1.4.0, https://CRAN.R-project.org/package=afc.

Corresponding BibTeX entry:

  @Manual{,
    title = {afc: Generalized Discrimination Score},
    author = {Andreas Weigel},
    year = {2017},
    note = {R package version 1.4.0},
    url = {https://CRAN.R-project.org/package=afc},
  }