Burundi issued sheet of stamps in 2011. It is four stamps in a mini-sheet. My version is not perforated. I am fairly certain a perforated version is available. This sheet is Scott #975. It shows Amadeus Mozart with a keyboard and musical score; Beethoven with organ pipes; Antonio Vivaldi with a violin; and Chopin with a piano. It seems there were also issued a set of 4 individual stamps, #971-974 showing the same composers but with different background elements. (Hans Timmerman's site shows the Beethoven stamp as a sheetlet of four identical stamps. It is denominated 1020 francs, rather than 1090 as described in Scott, and it has the same background (pipes) instead of the monument described in the catalog.) It may be possible to discern what organ is shown in the Beethoven stamp, but I am not able to figure it out. My version is in mint condition, from County Stamp Center.