To cite package ‘DPtree’ in publications use:

  Ning S (2018). _DPtree: Dirichlet-Based Polya Tree_. R package
  version 1.0.1, <https://CRAN.R-project.org/package=DPtree>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {DPtree: Dirichlet-Based Polya Tree},
    author = {Shaoyang Ning},
    year = {2018},
    note = {R package version 1.0.1},
    url = {https://CRAN.R-project.org/package=DPtree},
  }