To cite package ‘gettz’ in publications use:

  Eddelbuettel D (2022). _gettz: Get the Timezone Information_. R
  package version 0.0.5, , <https://github.com/eddelbuettel/gettz>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {gettz: Get the Timezone Information},
    author = {Dirk Eddelbuettel},
    year = {2022},
    note = {R package version 0.0.5, 
},
    url = {https://github.com/eddelbuettel/gettz},
  }