The Provisional Democratic Government in Greece also had a red triangle in the middle.
The Russian republic of the USSR was the Russian Soviet Federative Socialist Republic. You should accept that name, as well as its abbreviation (RSFSR) and also just 'Russia' since you accept 'Tajikistan', 'Lithuania', etc.
'USSR' should not be counted for the Ukrainian Soviet Socialist Republic. That acronym is only used for the Soviet Union. Instead, you should accept 'Ukraine' and 'Ukrainian SSR'.
The Russian republic of the USSR was the Russian Soviet Federative Socialist Republic. You should accept that name, as well as its abbreviation (RSFSR) and also just 'Russia' since you accept 'Tajikistan', 'Lithuania', etc.
'USSR' should not be counted for the Ukrainian Soviet Socialist Republic. That acronym is only used for the Soviet Union. Instead, you should accept 'Ukraine' and 'Ukrainian SSR'.