To cite package 'openCR' in publications use:

Efford, M. G. (2019). openCR: Open population capture-recapture models. R package version 1.4.1. https://CRAN.R-project.org/package=openCR

Corresponding BibTeX entry:

  @Manual{,
    title = {openCR: Open population capture-recapture models},
    author = {Murray Efford},
    year = {2019},
    note = {R package version 1.4.1},
    url = {https://CRAN.R-project.org/package=openCR},
  }