Russia's F-15 Killer: Why America (and the World) Fears the Su-27

It was the USSR’s best plane—and it still packs one heck of a punch. 

How Russia's Su-57 Felon Jets Compare to U.S. F-35, F-22 Fighters

How does Russia's SU-27 compare to the United States' F-15 Eagle? - Quora

Su-27 Flanker: The Story of Russia's F-15 Killer

Russian Su-27 Fighter Jet Collides With U.S. Drone Over Black Sea

Scary Video: Watch This Russian Su-27 Fighter Come Close to an American F-15C

Daily Briefing: War in Ukraine: Poland Says It Is Sending 4 Fighter Jets to Ukraine Within Days - The New York Times

The Truth About the MiG-29, Air & Space Magazine

Sukhoi Su-27 - Wikipedia

F-15 versus Flanker: An Eagle pilot's view

Did you know that the Soviet-era Su-27 was built on US F-15 technology? - Russia Beyond