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.

RS005.11

Country / Post Serbia
Date of Issue 9 February 2011
Primary theme Telecommunications
Subject 1866 Serbia becomes a Member of International Telecommunications Union (ITU)
Width 35.0 mm
Height 31.5 mm
Denomination 46 CSD
Number in set 1
Layout/Format sheet of 8
Perforations 13.25 by 13.25
Stamp issuing authority Public Enterprise of PTT Srbija
Printer Zin Belgrade