To cite the 'sirt' package in publications use:

Robitzsch, A. (2025). sirt: Supplementary Item Response Theory Models. R package version 4.2-133. https://CRAN.R-project.org/package=sirt

Corresponding BibTeX entry:

  @Manual{sirt_4.2-133,
    title = {sirt: Supplementary Item Response Theory Models},
    author = {Alexander Robitzsch},
    year = {2025},
    note = {R package version 4.2-133},
    url = {https://CRAN.R-project.org/package=sirt},
    doi = {10.32614/CRAN.package.sirt},
  }