To cite package 'HH' in publications use:

Richard M. Heiberger (2025). HH: Statistical Analysis and Data Display: Heiberger and Holland. R package version 3.1-53. URL https://CRAN.R-project.org/package=HH

To cite the HH book (second edition) in publications use:

Richard M. Heiberger and Burt Holland (2015). Statistical Analysis and Data Display: An Intermediate Course with Examples in R. Springer-Verlag, New York. URL https://link.springer.com/book/10.1007/978-1-4939-2122-5

To cite the HH book (first edition) in publications use:

Richard M. Heiberger and Burt Holland (2004). Statistical Analysis and Data Display: An Intermediate Course with Examples in S-Plus, R, and SAS. Springer-Verlag, New York. URL https://link.springer.com/book/10.1007/978-1-4757-4284-8

To cite likert from HH in publications use:

Richard M. Heiberger, Naomi B. Robbins (2014). Design of Diverging Stacked Bar Charts for Likert Scales and Other Applications. Journal of Statistical Software, 57(5), 1-32. URL https://www.jstatsoft.org/v57/i05/.

Corresponding BibTeX entries:

  @Manual{,
    title = {HH: Statistical Analysis and Data Display: Heiberger and
      Holland.},
    author = {Richard M. Heiberger},
    year = {2025},
    note = {R package version 3.1-53},
    url = {https://CRAN.R-project.org/package=HH},
  }

  @Book{,
    title = {Statistical Analysis and Data Display: An Intermediate
      Course with Examples in {R}},
    author = {Richard M. Heiberger and Burt Holland},
    year = {2015},
    publisher = {Springer-Verlag, New York},
    edition = {Second},
    url = {https://link.springer.com/book/10.1007/978-1-4939-2122-5},
  }

  @Book{,
    title = {Statistical Analysis and Data Display: An Intermediate
      Course with Examples in {S-Plus}, {R}, and {SAS}},
    author = {Richard M. Heiberger and Burt Holland},
    year = {2004},
    publisher = {Springer-Verlag, New York},
    edition = {First},
    url = {https://link.springer.com/book/10.1007/978-1-4757-4284-8},
  }

  @Article{,
    title = {Design of Diverging Stacked Bar Charts for Likert Scales
      and Other Applications},
    author = {Richard M. Heiberger and Naomi B. Robbins},
    journal = {Journal of Statistical Software},
    year = {2014},
    volume = {57},
    number = {5},
    pages = {1--32},
    doi = {10.18637/jss.v057.i05},
  }