To cite BayesPPD in publications use:

  Shen Y, Psioda MA, Ibrahim JG (2023). “BayesPPD: An R Package for
  Bayesian Sample Size Determination Using the Power and Normalized
  Power Prior for Generalized Linear Models.” The R Journal, 14(4).

A BibTeX entry for LaTeX users is

  @Article{,
    title = {BayesPPD: An R Package for Bayesian Sample Size Determination Using the Power and Normalized Power Prior for Generalized Linear Models},
    author = {Yueqi Shen and Matthew A. Psioda and Joseph G. Ibrahim},
    journal = {The R Journal},
    year = {2023},
    volume = {14},
    number = {4},
  }