To cite the hdrcde package in publications, please use:

Hyndman RJ (2018). hdrcde: Highest Density Regions and Conditional Density Estimation. R package version 3.3, http://pkg.robjhyndman.com/hdrcde.

Corresponding BibTeX entry:

  @Manual{,
    title = {{hdrcde}: Highest Density Regions and Conditional Density
      Estimation},
    author = {Rob J Hyndman},
    year = {2018},
    note = {R package version 3.3},
    url = {http://pkg.robjhyndman.com/hdrcde},
  }