Sentence:  [M]any of the African nations issuing the World Cup stamps have pandered to international collectors, with some stamps not even sold in the country of issue. These ‘<WSD>omnibus</WSD>' stamps featured topics and individuals with no links to the issuing country. African stamps displaying w:The Walt Disney Company 
Meaning of the word marked with <WSD> tags:  A stamp issue, usually commemorative, that appears simultaneously in several countries as a joint issue.