For a technical look at how organizations try to secure their domains, security.txt Revisited: Analysis of Prevalence and Conformity examines the adoption of standard security reporting methods.
Adopting a "Never Trust, Always Verify" approach for all data access requests. Download Mail Access MiX txt
Research on Features Analysis of All Email Components for Phishing Detection discusses how attackers lure victims into providing the credentials that eventually end up in these "MiX" lists. Defensive Best Practices For a technical look at how organizations try
If you are researching this to protect your own accounts from being included in such lists, experts recommend: Defensive Best Practices If you are researching this
The paper (PDF) Email Security Issues, Tools, and Techniques Used in Investigation reviews real-world email forensic incidents and the tools used to mitigate threats.
Essential for stopping hackers even if they have your password from a leaked "txt" file.