J Edgar Hoover Signed Letter
by Dave
(NY)
I have a letter on FBI stationary from June 1971. J Edgar is declining an invitation to an International Narcotic Enforcement Officer's annual conference. It's very similar to many I have seen online, both the size, letterhead, and signature.
The typewriter typeface is sans-serif. The 1950's through 1969 letters online are all an older serif style. The typing is very crisp and may be from a new typewriter and ribbon. Sans serif typefaces similar to this only appear in 1972 and later notes of his that I've seen online.
Source is the secretary to John Bellizzi, the head of the Association extending the invitation. The decline letter was not needed for files and was given to her as a souvenir of a summer job.