US Naval Institute on the Gulf of Tonkin: https://www.usni.org/magazines/naval-history-magazine/2008/february/truth-about-tonkin
Literally the NSA (click at own risk): https://www.nsa.gov/news-features/declassified-documents/gulf-of-tonkin/
The National Security Archive:
The History Channel: https://www.history.com/news/the-gulf-of-tonkin-incident-50-years-ago
Public Radio International: https://www.pri.org/stories/2017-09-14/what-really-happened-gulf-tonkin-1964
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