To cite BNPmix in publications use:

Corradin R, Canale A, Nipoti B (2021). “BNPmix: An R Package for Bayesian Nonparametric Modeling via Pitman-Yor Mixtures.” Journal of Statistical Software, 100(15), 1–33. doi:10.18637/jss.v100.i15.

Corresponding BibTeX entry:

    title = {{BNPmix}: An {R} Package for {B}ayesian Nonparametric
      Modeling via {P}itman-{Y}or Mixtures},
    author = {Riccardo Corradin and Antonio Canale and Bernardo
    journal = {Journal of Statistical Software},
    year = {2021},
    volume = {100},
    number = {15},
    pages = {1--33},
    doi = {10.18637/jss.v100.i15},