4c blue Colombian postal stationery envelope (H&G B17) franked with Russia 1929 10k+2k red brown & sepia and 20k+2k light blue & sepia 'Child Welfare' issue and 1930 '25th Anniversary of 1905 Rebellion' set of three (SG 536/537 & 576/578) tied by AIRMAIL USSR LENINGRAD - BERLIN illustrated 'Airplane' cancel in black dated 5. V. 1931 with added Colombia 1917 2 x 1c green & 2c carmine National issue (SG 358/359) and 1929 5c orange yellow, 10c red brown & 15c green SCADTA issue (SG 56/58) all tied by BUENAVENTURA SCADTA cds's dated 25. V. 1931. Flown on the 'Reopening of the Leningrad-Berlin Air Route' with two line 'Erstflug 1931 Wiedereroffnung de Fluglinie: Leningrad - Berlin' cachet in red. Addressed to CALI, COLOMBIA with green 'SCADTA' airmail label plus BERLIN airmail service marking in red all on front and other transit marks on reverse. Very attractive and scarce. (Muller Unlisted)