@Manual{R,
    title = {R: A Language and Environment for Statistical Computing},
    author = {{R Core Team}},
    organization = {R Foundation for Statistical Computing},
    address = {Vienna, Austria},
    year = {2017},
    url = {https://www.R-project.org/},
  }

@misc{unicode,
year={2018},
author={{The Unicode Consortium}},
title={ The Unicode Standard},
howpublished={\url{http://www.unicode.org/versions/latest/}}
}