To cite package ‘flipdownWidgets’ in publications use:

Fang Y (2021). flipdownWidgets: A Wrapper of JavaScript Library 'flipdown.js'. R package version 0.1.0, https://github.com/fanggong/flipdownwidgets.

Corresponding BibTeX entry:

  @Manual{,
    title = {flipdownWidgets: A Wrapper of JavaScript Library
      'flipdown.js'},
    author = {Yongchao Fang},
    year = {2021},
    note = {R package version 0.1.0},
    url = {https://github.com/fanggong/flipdownwidgets},
  }