https://www.youtube.com/watch?v=xwFQfKvKs3w
7 histórias intrigantes de OVNIs avistados na União Soviética – Fatos Desconhecidos
avistamentos de ufos na União Soviética - Pesquisar (bing.com)
https://www.cia.gov/readingroom/search/site/ussr%20ufo
https://ufo.com.br/1989-o-ano-em-que-os-ufos-quase-invadiram-a-uniao-sovietica/
https://www.dailymail.co.uk/sciencetech/article-12332257/Newly-declassified-intelligence-documents-reveal-CIA-officials-saw-two-flying-disc-UFOs-Soviet-Union-Cold-War.html