United Nation Postal Administration Endangered Species issues have been issued from the 90's to date.   All three offices, New York, Geneva and Vienna participate.  If you note the denomination on the stamps you can tell which office, New York in cents (c), Geneva in Franks (FS), and Vienna in Schilling (S) and Euros (E).  These are wonderful First Day of Issue envelopes with great artwork.  The back of each of these have descriptions in detail about each individual from the animal and plant kingdom.   An example is shown in the second image, it is Giant Panda.  Every item is in fresh and clean condition.