Have a look at the references listed in this article: https://en.wikipedia.org/wiki/1%25_rule#:~:text=2%20Participation%20inequality-,Definition,forum%20but%20

Have a look at the references listed in this article: https://en.wikipedia.org/wiki/1%25_rule#:~:text=2%20Participation%20inequality-,Definition,forum%20but%20do%20not%20post https://en.wikipedia.org/wiki/1%25_rule#:~:text=2%20Particip....