Margin overprint change: the same margin of sheets issued chronologic with different margin overprints |
Margin overprint introduction: the same margin of sheets issued chronologic without and than with margin overprint |
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Edition 1976: without margin overprint |
Edition 1980: with margin overprint |
Margin overprint text change: the same margin of sheets issued chronologic with different margin overprint texts |
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The same postage stamps with different row number overprints |