Stamps with the theme U.P.U. - - The free
Postage Stamps 1949 Universal Postal Union Omnibus Issue
This stamp has been designated as Scott Number C42. The UPU's headquarters continue to be located in Bern, Switzerland.
Ten Universal Postal Union Airmail US Postage Stamps - No. C42
Sets may have variation in perforations or centering.
371 & 372 MNH Canadian stamps - 1957 UPU Congress set
Postage Stamps 1949 Universal Postal Union Omnibus Issue
UPU coordinates worldwide postal services
South Vietnam- Original Vintage Postage Stamps - 1974 UPU Postal
Postage Stamps 1949 Universal Postal Union Omnibus Issue
Universal Postal Union
The new face of philately