Here you go, straight from J. Edgar's boys to you:
https://leb.fbi.gov/file-repository/...tober-1969.pdf
This is a PDF of the whole LE bulletin, so when the article is continued you will have to scroll to page 20 to finish.
Old stuff, but still relevant, the FBI used to send out reprints of the article in a brochure form, we discussed and demoed in our firearms instructor course for years. Ultimately, time constraints and additional material relegated the handout to a mention and admonition to 'study this handout.'