21. When citizens are issued a new passport, the first revenue stamp , or bollo, is included. 22. Other countries have simply allowed revenue stamps to be used for postage or vice versa. 23. Joyce wrote numerous articles on the results of his studies of United States revenue stamps . 24. Revenue stamps were also issued, see Revenue stamps of the Federation of Rhodesia and Nyasaland. 25. His philatelic interests lie in revenue stamps and the large key plate stamps of Nyasaland. 26. It has also been used on revenue stamps and postal stationery, including International Reply Coupons. 27. Canada issued revenue stamps from 1864 to 2005. 28. Three distinct revenue stamp series were produced to pay the taxes during that twenty one-year period. 29. They discovered that the lot contained a gold mine of revenue stamps , including unused ones. 30. He was an expert on the postage stamps of Finland and the revenue stamps of Ecuador.