Kevin,
you can find some info about those here:
http://www.ruettinger-web.de/e-pelikan-modell-limited.htmlHere is what Dittmer and Lehman say about those in their book "Pelikan Writing Instruments: 1929-2004":
"An event of a very special nature was the world exhibition that took place in 2000, in Pelikan's hometown, Hannover: Expo 2000. It was clear that the company would use the opportunity to bring out a limited edition under that very name. The exhibition's motto was: "Humankind, Nature, Technology". Three different Toledo overlays were developed. In 1998, Pelikan introduced the first edition of 1,998 pieces with an illustration on the overlay of the famous "double helix" of DNA, the carrier of our hereditary information. In 1999 followed the second edition, this time 1,999 pieces, with an illustration fo the ammonite, one of the most primitive forms of life on earth, and, to close the circle, the year 2000 saw the arrival of the third limited edition, this time of 2,000 pieces, with the symbol of today's technology, the computer chip, as illustration on the sleeve."
Best,
Riccardo