To cite 'fwildclusterboot' in publications use:

  Fischer & Roodman. (2021). fwildclusterboot: Fast Wild Cluster
  Bootstrap Inference for Linear Regression Models. Available from
  https://cran.r-project.org/package=fwildclusterboot.

A BibTeX entry for LaTeX users is

  @Misc{,
    title = {fwildclusterboot: Fast Wild Cluster Bootstrap Inference for Linear Regression Models (Version 0.14.3)},
    author = {Alexander Fischer and David Roodman},
    year = {2021},
    url = {https://cran.r-project.org/package=fwildclusterboot},
  }