“23.11.83. The Office for Foreign Assets Control of the Treasury Department announced that it had reasons to believe that certain materials with nickel content imported from the USSR contain Cuban nickel. The note included the detention at Customs of materials directly or indirectly imported from the USSR and that consideration was given to the requirement that imports into the United States of certain nickel materials from countries that import from the USSR should be accompanied by documents showing that they were not manufactured in the USSR or with Soviet nickel.” [Pro Embargo]
“Ronald W. Reagan (R). Timeline,” Cuba versus Blockade: Cuban People’s website, 2007