To cite package ‘cstime’ in publications use:

  Zhang C, White RA (2025). _cstime: Date and Time Functions for Public
  Health Purposes_. R package version 2025.10.13,
  <https://CRAN.R-project.org/package=cstime>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {cstime: Date and Time Functions for Public Health Purposes},
    author = {Chi Zhang and Richard Aubrey White},
    year = {2025},
    note = {R package version 2025.10.13},
    url = {https://CRAN.R-project.org/package=cstime},
  }