To cite package ‘NPCDTools’ in publications use:

Chiu C, Xiao W, Köhn H, Wang Y, Wen X (2026). NPCDTools: The Nonparametric Classification Methods for Cognitive Diagnosis. R package version 1.1.0, https://CRAN.R-project.org/package=NPCDTools.

Corresponding BibTeX entry:

  @Manual{,
    title = {NPCDTools: The Nonparametric Classification Methods for
      Cognitive Diagnosis},
    author = {Chia-Yi Chiu and Weixuan Xiao and Hans Friedrich Köhn and
      Yu Wang and Xiran Wen},
    year = {2026},
    note = {R package version 1.1.0},
    url = {https://CRAN.R-project.org/package=NPCDTools},
  }