To cite package ‘ymd’ in publications use:

  Tan X (2024). _ymd: Parse 'YMD' Format Number or String to Date_. R
  package version 0.1.4, <https://CRAN.R-project.org/package=ymd>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {ymd: Parse 'YMD' Format Number or String to Date},
    author = {Xianying Tan},
    year = {2024},
    note = {R package version 0.1.4},
    url = {https://CRAN.R-project.org/package=ymd},
  }