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On September 21, 2018, the Spanish Post issued a postage stampto honour the 150th anniversary of the death of of General Leopoldo O’Donnell y Jorris (1809-1867).
On September 18, 2018, the Luxembourg Post issued a stamp in honor of Postage Stamp Day.
On September 7, 2018, the Latvian Post issued a commemorative postage stamp "Curonian Kings".