I published an article entitle entitled "The WADP Numbering System (WNS)" in Philateli-Graphics 29:2 (April 2007). In this article, I describe how the
WNS works, and I advocate that philatelists should make greater use of it to
view and research stamps. To view the article in PDF format, click here. After the article was published, I sent a copy of it to the Universal Postal
Union. If you click here, you will be able to see the UPU's response to
me.