1941, First Flight Liberia - US, black surcharge 50c on 1c green, nicely centered, full OG, light trace of hinge, VF and very rare, only 43 stamps were produced, several guarantee hs on reverse, including J. Stolow, C.v.$3,250, Est. $1,200-$1,500 (Image)

1941, First Flight Liberia - US, black surcharges 50c on 2c, 3c, 4c, 5c, 10c and 30c or overprints on 50c and $1, set of eight values (no 50c/20c), full OG, NH or VLH (No.C19), VF and scarce assemblage, each stamp with expert's sign, C.v. $910 as hinged, Est. $500-$600 (Image)

1941, First Flight Liberia - US, inverted surcharge 50c on 2c red orange and inverted overprint on $1blue, full OG, NH or LH (2c), VF, each one with experts' signs, C.v. $300 as hinged, Est. $150-$200 (Image)

1944-45, Local surcharges on Air Post stamps of 1938, set of six, including 30c on 3c olive green, in addition horizontal pair of 10c/2c red orange, left stamp without the surcharge, all with full OG, NH or LH (pair, 30c/3c and 30c/4c), VF, each stamp with experts' signs, C.v. $383 as hinged (pair counted as two singles), Est. $250-$300 (Image)