If you ever have the opportunity to get the full sheet of these from all 3 issuing offices at anything close to face value, you should go for it. Even thought the pairs are identical, the sheets were a quick sellout because of the continuous horizontal design, and most of the subscribers only got the pairs. The full sheets have a significantly higher premium, and are one of the few UN items from the 1980s that have a significant premium.
It's a really pretty stamp! Congratulations!

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