1905, Russo-Japanese War military postcard from 16th Aviation Park of Artillery Brigade addressed to Volkovysk (then Russian Poland), FPO ''26.V.1905'' date stamp and arrival marking is alongside, mostly VF. Such Aviation Units (mainly small airships, blimps and balloons) were created in both Armies for reconnaissance and fire adjustment, Est. $150-$200 (Image)

1905, Russo-Japanese War military postcard from the 1st Aviation Artillery Park of the 36th Artillery Brigade addressed to Moscow, Harbin Train Station entry date stamp and arrival marking is alongside, mostly VF and scarce, Est. $150-$200 (Image)

1915, the World War I military postcard from the Office of the Head of Aviation and Aeronautics in the Active Forces, addressed to Moscow, mostly VF and scarce, Est. $100-$150 (Image)

1916, the World War I military postcard from the 3rd Observation Station of the 7th Aeronautical Company, addressed to Kharkov, machine arrival marking, F/VF and scarce, Est. $150-$200 (Image)

1930, Moscow Zeppelin Flight, 40k ultra and 80k carmine, imperforated complete set of two in horizontal pairs, beautiful margins all around, full OG, previously hinged, VF and rare, especially in pairs, expertized by Z. Mikulski and others, C.v. $6,600 as singles, Est. $4,000-$5,000 (Image)

1932, Airship over the Dnieper Dam, 15k gray black, engraved printing, perforation 10½, nice centering and intact perforation for this difficult stamp, full OG, previously hinged, VF, C.v. $2,000, Est. $1,000-$1,500 (Image)

1934, Civil Aviation, 5k-80k, complete set of five printed on paper without watermark, full OG, LH or previously hinged, VF, Est. $150-$200 (Image)

1916, blue diagonal overprint ''Kitai'' on 1r brown, dark brown and orange, perforation 12½ instead of 13½, practically complete Russian PO in Shanghai cancellation, VF and scarce, PF certificate, the stamp is listed in the M. Kramarenko Cat. #39 IIA, C.v. $650, Est. $200-$300 (Image)

MAINLY REFERENCES GROUP: 1899-1920, 138 mint and used stamps, representing all Russian issues for Chinese Offices, including 15 or so inverted ''Kitai'' overprints all either obvious forgeries or look dubious, several overprints in colors, which never exist, some nice and valuable items, such as ''Dollars'' surcharges on the high values, used Harbin surcharge 10c over 10k/7k and others, full/large part of OG or used, F/VF, Est. $250-$350 (Image)

1903-05, diagonal blue surcharge 10pi on 1r brown, pale brown and orange printed on vertically laid paper, right sheet margin imperforated (!) single, a part of perfin Obrazets at top left, full OG, LH, VF and scarce, Est. $200-$250 (Image)

CLEAN AND VALUABLE UNIT: 1879-1913, over 450 mint and used stamps, starting with Numerals on laid paper, then early surcharges and 50th Anniversary of the R.O.P.i T., all complete sets of City overprints, including numerous varieties, surcharges on Romanov Dynasty with duplicates, later issues with complete sheet of No.202 and 14 Wrangel's Army stamps, fresh condition, full/large part of OG or used, F/VF, C.v. is over $3,600, Est. $1,000-$1,200 (Image)

OUTSTANDING HOLDING OF ''ODESSA'' AND ''WILD LEVANT'' ISSUES : 1919-21, 445 stamps of R.O.P.i T. overprints and surcharges with numerous varieties in singles, pairs and blocks, then over 400 stamps representing Numerals, including complete pane of 20pa brown, and R.O.P.i T. Arms in various colors in two different sizes (so-called ''Wild Levant''), including tete-beche pairs and blocks, stamp with inverted Arms and etc., fresh quality unit, full OG or no gum as issued, F/VF, Est. $600-$800 (Image)

1924, red surcharge 10k on 35k ultra, left margin block of four, top left stamp without the surcharge, full OG, NH, VF, C.v. $550 for a hinged pair with and without surcharge, Est. $200-$300 (Image)

1922, Philately for the Children, inverted black overprint on imperforated 1k orange with kiss double impression, second printing, position 5 of not inverted setting, full OG, NH, VF and scarce, Soviet Philatelic guarantee hs, Est. $500-$600 (Image)

1923, Philately for the Labor, bronze surcharge with spaced date ''1 923'' 4r+4r on 5000r violet, full OG, LH, VF, expert's sign on reverse, Est. $250-$300 (Image)