1930 (26 Jun) USSR Leningrad - Frankfurt, Airmail Registered cover, flight Leningrad - Riga, Riga - Berlin, Berlin - Frankfurt (Foreign Philatelic Exchange surcharge on back, Label 'Application 728', Muller 20 and 236, CV $950)

From ex Dr. Peter Moeller collection that received the Large Gold Medal at the Hannover 2011 Exhibition.

With the start of the 1930 flying season, two DERULUFT connections from Berlin to the USSR:

Berlin - Königsberg - Kaunas - Moscow
Berlin - Königsberg - Riga - Reval - Leningrad

Leningrad - Berlin - (Frankfurt)

Postmark:
Leningrad TSt 26.6.1930 .
Leningrad St 27.6.1930
Berlin 28.6.1930
Berlin MLb
Frankfurt 28.6.1930
Frankfurt MLb

Additional postmark:
The North.Western / Division of Soviet / Philatelic Association / USSR Leningrad, pr. 25.October, 60

Reverse side:
Control stamps for philatelic consignments and yellow control stamp with control number and imprint "Beilage" (Russian)

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Mit Beginn der Flugsaison 1930 entstanden zwei DERULUFT-Verbindungen von Berlin in die UdSSR:
Berlin — Königsberg — Kaunas — Moskau
Berlin — Königsberg — Riga — Reval — Leningrad

Leningrad - Berlin — (Frankfurt)

Poststempel:
Leningrad TSt 26.6.1930 .
Leningrad St 27.6.1930
Berlin 28.6.1930
Berlin MLb
Frankfurt 28.6.1930
Frankfurt MLb

Zusatzstempel:
The North.Western / Division of Soviet / Philatelic Association / USSR Leningrad, pr. 25.October, 60

Rückseite:
Kontrollmarken für philatelistische Sendungen und gelbe Kontrollmarke mit Kontrollnummer und Aufdruck „Beilage” (russisch)