wheelman: if you plan to get serious about early Persian issues, you will need a Persiphila catalogue (www.persi.com).
I have this in paperback, which unfortunately is sold out:
www.persi.com/books/persicat2002/index.htmlThe hardback is $75, and a different, later edition is more. You might check with a used philatelic bookseller like Leonard Hartmann
www.pbbooks.comThis link gives a bit more information:
www.persi.com/forgeries/1902...ts/index.htmlThe Serrane Guide, published by the APS, doesn't cover this issue other than saying do comparison. Focus on Forgeries, by the late Varro E. Tyler, covers the 1906 issue, not 1902. Hope this helps. Steve