Auction #93 Worldwide Air Post stamps and postal history, Zeppelin Flight items, philatelic rarities of the World

1993, National Postal Museum, 29c multicolored, bottom right corner sheet margin plate No.444334 imperforated se-tenant block of four, minor marginal wave at the bottom selvage, full OG, NH, VF and very rare, C.v. $2,500, Est. $1,000-$1,200