To cite ConjointChecks package in publications use:

  Domingue B (2012). ConjointChecks: A package to check the
  cancellation axioms of conjoint measurement. (R package version
  0.2.0) URL: https://github.com/ben-domingue/ConjointChecks

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {{ConjointChecks}: A package to check the cancellation axioms of conjoint measurement.},
    author = {Benjamin Domingue},
    year = {2012},
    note = {R package version 0.2.0},
    url = {https://github.com/ben-domingue/ConjointChecks},
  }