To cite psychomix in publications please use:

  Frick H, Strobl C, Leisch F, Zeileis A (2012). “Flexible Rasch
  Mixture Models with Package psychomix.” _Journal of Statistical
  Software_, *48*(7), 1-25. doi:10.18637/jss.v048.i07
  <https://doi.org/10.18637/jss.v048.i07>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Flexible Rasch Mixture Models with Package {psychomix}},
    author = {Hannah Frick and Carolin Strobl and Friedrich Leisch and Achim Zeileis},
    journal = {Journal of Statistical Software},
    year = {2012},
    volume = {48},
    number = {7},
    pages = {1--25},
    doi = {10.18637/jss.v048.i07},
  }

If you use Rasch mixture models with a restricted score distribution,
please additionally cite:

  Frick H, Strobl C, Zeileis A (2015). “Rasch Mixture Models for DIF
  Detection: A Comparison of Old and New Score Specifications.”
  _Educational and Psychological Measurement_, *75*(2), 208-234.
  doi:10.1177/0013164414536183
  <https://doi.org/10.1177/0013164414536183>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{R}asch Mixture Models for {DIF} Detection: A Comparison of Old and New Score Specifications},
    author = {Hannah Frick and Carolin Strobl and Achim Zeileis},
    journal = {Educational and Psychological Measurement},
    year = {2015},
    volume = {75},
    number = {2},
    pages = {208--234},
    doi = {10.1177/0013164414536183},
  }