@Manual{wickham_dplyr_2016,
	title = {dplyr: A Grammar of Data Manipulation},
	url = {https://CRAN.R-project.org/package=dplyr},
	author = {Hadley Wickham and Romain Francois and Lionel Henry and Kirill Müller},
	year = {2017},
	note = {R package version 0.7.4}
}

@article{daniel_ludecke_2018_1249192,
  author       = {Daniel Lüdecke},
  title        = {sjmisc: Data and Variable Transformation Functions},
  month        = {May},
  year         = {2018},
  doi          = {10.5281/zenodo.1249192},
  url          = {https://doi.org/10.5281/zenodo.1249192},
  publisher    = {Zenodo}
}

@article{daniel_ludecke_2018_1249216,
  author       = {Daniel Lüdecke},
  title        = {sjlabelled: Labelled Data Utility Functions},
  month        = {May},
  year         = {2018},
  doi          = {10.5281/zenodo.1249216},
  url          = {https://doi.org/10.5281/zenodo.1249216},
  publisher    = {Zenodo}
}

@Manual{haven,
  title = {haven: Import and Export 'SPSS', 'Stata' and 'SAS' Files},
  author = {Hadley Wickham and Evan Miller},
  year = {2018},
  note = {R package version 1.1.1},
  url = {https://CRAN.R-project.org/package=haven}
}
