The World Association for the Development of Philately (WADP) and the Universal Postal Union (UPU) jointly conceived and developed the WADP Numbering System - WNS, which was launched on 1 January 2002.

PT068.12

Country / Post Portugal
Date of Issue 19 June 2012
Primary theme Olympic Games (Summer Olympics)
Subject Olympic Games London 2012
Width 30.6 mm
Height 40.0 mm
Denomination N 20g
Number in set 4 (show set)
Layout/Format sheet of 50
Perforations 13 by 13
Stamp issuing authority CTT Correios de Portugal SA
Printer Imprensa Nacional Casa da Moeda
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