To cite package ‘cem’ in publications use:

Iacus S, King G, Porro G, Nielsen R (2022). cem: Coarsened Exact Matching. R package version 1.1.31, https://CRAN.R-project.org/package=cem.

Corresponding BibTeX entry:

  @Manual{,
    title = {cem: Coarsened Exact Matching},
    author = {Stefano M. Iacus and Gary King and Giuseppe Porro and
      Richard Nielsen},
    year = {2022},
    note = {R package version 1.1.31},
    url = {https://CRAN.R-project.org/package=cem},
  }