To cite pdp in publications use:

Greenwell BM (2017). “pdp: An R Package for Constructing Partial Dependence Plots.” The R Journal, 9(1), 421–436. doi:10.32614/RJ-2017-016, https://doi.org/10.32614/RJ-2017-016.

Corresponding BibTeX entry:

  @Article{,
    title = {pdp: An {R} Package for Constructing Partial Dependence
      Plots},
    author = {Brandon M. Greenwell},
    journal = {The R Journal},
    year = {2017},
    volume = {9},
    number = {1},
    pages = {421--436},
    url = {https://doi.org/10.32614/RJ-2017-016},
    doi = {10.32614/RJ-2017-016},
  }