I do not believe for a minute, that you even bothered to click on any of them. You are too closed-minded to put forth even a moment's worth of effort to enlighten yourself. This is the Grumpy Old Men from Mayberry forum. The 1960's are over. Mail-in balloting isn't going away.
These were the 5 sources that I used :
1) The Conversation
2) The Brennan Center
3) Columbia University
4) The National Conference of State Legislatures
5) San Diego Union Tribune
* In case you are unfamiliar with Conversation.com, it was founded in Melbourne, Australia in 2011, to serve as a network of not-for-profit media outlets publishing news stories and research reports online, with accompanying expert opinion and analysis. The articles which appear are written by academics and researchers; not political pundits or journalists.