To cite popbayes in publications use:

Casajus Nicolas, Pradel Roger (2022). popbayes: Bayesian model to estimate population trends from counts series. R package version 1.1, https://frbcesab.github.io/popbayes/.

Corresponding BibTeX entry:

  @Manual{,
    title = {popbayes: Bayesian model to estimate population trends
      from counts series},
    author = {{Casajus Nicolas} and {Pradel Roger}},
    year = {2022},
    note = {R package version 1.1},
    url = {https://frbcesab.github.io/popbayes/},
  }