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D
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J
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K
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O
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P
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Q
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R
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T
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U
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V
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W
- Wallis and Futuna Islands
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Y
- Yemen Arab Republic
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Z
- Zaire
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Czechoslovakia: Union of Czechoslovakian Mathematicians & Physicists
Issued: 6 July 1987

the Prague Town Hall mathematical clock and a function graph

Scott #2663
Last Modified: 2008-07-30