To cite touch in publications use:

Wang W, Li Y, Yan J (2018). touch: Tools of Utilization and Cost in Healthcare. R package version 0.1-6, https://CRAN.R-project.org/package=touch.

Corresponding BibTeX entry:

  @Manual{,
    title = {{touch}: {T}ools of Utilization and Cost in Healthcare},
    author = {Wenjie Wang and Yan Li and Jun Yan},
    note = {{R} package version 0.1-6},
    year = {2018},
    url = {https://CRAN.R-project.org/package=touch},
  }