To cite PowerUpR in publications use:

Bulus, M., Dong, N., Kelcey, B., & Spybrook, J. (2019). PowerUpR: Power Analysis Tools for Multilevel Randomized Experiments. R package version 1.0.4. https://CRAN.R-project.org/package=PowerUpR

Corresponding BibTeX entry:

  @Manual{,
    title = {{PowerUpR}: Power Analysis Tools for Multilevel Randomized
      Experiments},
    author = {Metin Bulus and Nianbo Dong and Benjamin Kelcey and
      Jessaca Spybrook},
    note = {R package version 1.0.4},
    year = {2019},
    url = {https://CRAN.R-project.org/package=PowerUpR},
  }