To cite npi in publications, please use:

Farach F (2022). npi: Access the U.S. National Provider Identifier Registry API. doi:10.5281/zenodo.6326729. R package version 0.3.0, https://github.com/ropensci/npi.

Corresponding BibTeX entry:

  @Manual{,
    title = {{npi}: Access the U.S. National Provider Identifier
      Registry API},
    author = {Frank Farach},
    url = {https://github.com/ropensci/npi},
    year = {2022},
    doi = {10.5281/zenodo.6326729},
    note = {R package version 0.3.0},
  }