To cite the hdrcde package in publications, please use:
Hyndman RJ, Einbeck J, Wand MP (2021). hdrcde: Highest Density Regions and Conditional Density Estimation. R package version 3.4, https://pkg.robjhyndman.com/hdrcde/.
Corresponding BibTeX entry:
  @Manual{,
    title = {{hdrcde}: Highest Density Regions and Conditional Density
      Estimation},
    author = {Rob J Hyndman and Jochen Einbeck and Matthew P Wand},
    year = {2021},
    note = {R package version 3.4},
    url = {https://pkg.robjhyndman.com/hdrcde/},
  }