1. The state of the email address
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3. Md. Ishtiaq Ashiq, Weitong Li, Tobias Fiebig, and Taejoong Chung. 2023. You've Got Report: Measurement and Security Implications of DMARC Reporting. In Proceedings of the 32nd USENIX Security Symposium. Anaheim, CA, USA, 4123--4137.
4. Barracuda. 2023 a. Email Security Gateway. (Sept. 2023). https://www.barracuda.com/products/email-protection/email-security-gateway