1931, Airship over the Arctic Region, 50k dark gray blue, error of color, full OG, previously hinged, fine stamp, C.v. $500

1931, Ice-Breaker ''Malygin'' (North Pole Zeppelin Flight), 30k-2r, imperforated complete set of four, balanced margins, full OG, NH, VF, C.v. $217

1934, 80k purple, a single with perforation 10x14x14x14, printed on watermarked paper, rough perforation at top as always on these errors, neat Moscow CTO with full OG, VF and rare, N. Mandrovski certificate

1935, Chelyuskin Rescue, 1k-50k, complete set of ten, nicely centered, full OG, mainly VLH including 25k and 50k, 30k is previously hinged, VF, C.v. $1,032

1935, Chelyuskin Rescue, 1k-50k, complete set of ten, fresh condition, unused, expertly regummed with no hidden defects, VF appearance

1935, Moscow – San Francisco Flight, red surcharge 1r on 10k dark brown, position 17 of 25-stamp setting, full OG, NH, VF, Soviet Philatelic guarantee on reverse, C.v. $1,275

1935, Moscow – San Francisco Flight, red surcharge 1r on 10k dark brown, position 18 of 25-stamp setting, full OG, NH (2mm spot of gum disturbance in the middle of stamp), VF, Soviet Philatelic guarantee hs, C.v. $1,275

1935, Moscow – San Francisco Flight, red surcharge 1r on 10k dark brown, position 2 (missing leg of ''r'' in Francisco), several slight yellow spots on reverse, full OG, LH, VF centering, Soviet Philatelic guarantee hs, C.v. $725

1935, Moscow – San Francisco Flight, red surcharge 1r on 10k dark brown, small ''f'' variety, position 9 of 25-stamp setting, full OG, VLH, VF, Soviet Philatelic guarantee hs, Rossika certificate, C.v. $1,500

1935, Moscow – San Francisco Flight, red surcharge 1r on 10k dark brown, small ''f'' variety of surcharge, position 10, full OG, VLH, VF, Soviet Philatelic guarantee on reverse, C.v. $1,500

1937, Aviation Exhibition, 1r black, brown and buff, souvenir sheet of four, fresh condition, full OG, NH, VF, C.v. $450

1937, Aviation Exhibition, 1r black, brown and buff, souvenir sheet of four, retouch of the upper right stamp at top band, nice quality, full OG, NH and rather scarce

1955, North Pole – Moscow Flight, red overprint on definitive stamp of 2r black and yellow green, perforation L12½ instead of comb 12x12½, top sheet margin block of four, full OG, NH, VF

GROUP OF THREE PIONEER FLIGHTS: 1926-32, two covers delivered on air mail line ''Moscow – Berlin'' (one addressed to Wilmersdorf and has non-air post franking, the other one – to Brussels), the last one is postcard ''Franz Joseph Land – Arkhangelsk'' with 50k franking, each one with appropriate markings and mainly VF