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 EC022.16

  1. Ec020.16-80
    Wns Number
    EC020.16
    Country / Post
    Ecuador
    Date of Issue
    October 25, 2016
    Subject
    Coca Codo Sinclair Hydroelectric Plant
  2. Ec021.16-80
    Wns Number
    EC021.16
    Country / Post
    Ecuador
    Date of Issue
    October 25, 2016
    Subject
    Coca Codo Sinclair Hydroelectric Plant
  3. Ec022.16-80
    Wns Number
    EC022.16
    Country / Post
    Ecuador
    Date of Issue
    October 25, 2016
    Subject
    Coca Codo Sinclair Hydroelectric Plant