The stamp exhibition was scheduled to be held in Chicago from May 22 to June 1, 1986, and China had planned to participate, but because of the Taiwan issue, China cancelled its plans to participate in the stamp exhibition.
The China Philatelic Corporation originally planned to issue a WZ-37 commemorative cover (the WZ37 on the catalog is now China's participation in the Stockholm International Philatelic Exhibition in Sweden):
The back of the souvenir cover
The China Philatelic Corporation also issued a commemorative sheet for the stamp exhibition (printed by the North American Distribution Bureau of China Stamps) for nailing in the exhibit catalogue issued by the stamp exhibition, after which the Chinese party asked the organizer to tear off all the commemorative sheets in the exhibit catalog:
Commemorative Zhang
However, for some reason, the souvenir sheet issued by the Chinese party in some exhibit catalogs was not torn off and sold to philatelists:
Catalog cover
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