National Security Agency (2017). Russia/Cybersecurity: Main Intelligence Directorate Cyber Actors, Target U.S. Companies and Local U.S. Government Officials Using Voter Registration-Themed Emails, Spoof Election-Related Products and Services, Research Absentee Ballot Email Address.
https://www.documentcloud.org/documents/3766950-NSA-Report-on-Russia-Spearphishing

has been cited by the following article: