To cite package ‘volker’ in publications use:

  Jünger J, Kotthoff H (2024). _volker: High-Level Functions for
  Tabulating, Charting and Reporting Survey Data_. R package version
  3.0.0, <https://CRAN.R-project.org/package=volker>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {volker: High-Level Functions for Tabulating, Charting and Reporting
Survey Data},
    author = {Jakob Jünger and Henrieke Kotthoff},
    year = {2024},
    note = {R package version 3.0.0},
    url = {https://CRAN.R-project.org/package=volker},
  }