The following are references to the package. You should also reference the individual methods used, as detailed in the reference section of the help files for each function.

Hofmeyr DP, Pavlidis NG (2019). “PPCI: an R Package for Cluster Identification using Projection Pursuit.” The R Journal. doi: 10.32614/RJ-2019-046, https://journal.r-project.org/archive/2019/RJ-2019-046/index.html.

To get Bibtex entries use: x<-citation("PPCI"); toBibtex(x)

Corresponding BibTeX entry:

  @Article{,
    title = {{PPCI}: an {R} Package for Cluster Identification using
      Projection Pursuit},
    author = {David P. Hofmeyr and Nicos G. Pavlidis},
    journal = {{The R Journal}},
    year = {2019},
    doi = {10.32614/RJ-2019-046},
    url =
      {https://journal.r-project.org/archive/2019/RJ-2019-046/index.html},
  }