cover 1929 (30 Nov.) envelope (philatelic) from Altan Bulak to Harbin bearing 5m., 20m. and 25m. with Third Definitive 1m. pairs (2) cancelled by double ring d.s., without Chinese adhesives but showing arrival c.d.s.; 1929 (31 Dec.) native envelope from Ulan Bator to Peking bearing 20m. with Third Definitive 1m. (5) in combination with "Junk" 10c. cancelled by "HARBIN" c.d.s. in transit and 1930 (11 jan.) registered envelope from Ulan Bator to Harbin bearing 5m. pair, 20m. and Third Definitive 50m. with, on reverse, Postage Due 10c. (5) applied on arrival