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.

Stamps issued with PY013.04

  1. Py012.04-80
    Wns Number
    PY012.04
    Country / Post
    Paraguay
    Date of Issue
    August 26, 2004
    Subject
    25th Anniversary of the Clay Museum
  2. Py013.04-80
    Wns Number
    PY013.04
    Country / Post
    Paraguay
    Date of Issue
    August 26, 2004
    Subject
    25th Anniversary of the Clay Museum
  3. Py014.04-80
    Wns Number
    PY014.04
    Country / Post
    Paraguay
    Date of Issue
    August 26, 2004
    Subject
    25th Anniversary of the Clay Museum