Here are few airmail labels from East Germany.
The German Democratic Republic (GDR; German: Deutsche Demokratische Republik or DDR), informally called East Germany by West Germany and other countries, was the socialist state established in 1949 in the Soviet zone of occupied Germany and in the East Berlin portion of the Allied-occupied capital city. The German Democratic Republic, which consisted geographically of northeast Germany rather than all of eastern Germany, had an area of 107,771 km2 (41,610 mi2), bordering Czechoslovakia in the south, West Germany (officially: Federal Republic of Germany) in the south and west, the Baltic Sea to the north, and Poland in the east.(Wikipedia).
Year: 1957, Gummed. Günter Mair's catalogue no: - GDR-B-1a.
Interflug (Interflug GmbH, Gesellschaft für Internationalen Flugverkehr mbH) was the state airline of East Germany from 1963 to 1991, when it ceased operations following German reunification. Originally, the East German national airline was called Deutsche Lufthansa (officially Deutsche Lufthansa GmbH der DDR), but this met opposition from West Germany, with a court case in Bern awarding the Lufthansa trademark to the West German company.(Wikipedia)
Year: 1975, Gummed. Günter Mair's catalogue no: - GDR-B-4.
Year: 1971, Gummed. Günter Mair's catalogue no: - GDR-B-3.
Year: 1965, Gummed. Günter Mair's catalogue no: - GDR-B-2c