An Interesting Error on Bird Defintive Stamp

Finding error stamps from post offices is a difficult task for odinary collectors. Most of the time the major error stamps fall on the hands of dealers. I do not know what do say as I had a luck to obtain a major error stamp block from one post office. The original stamp is one of the definitive bird stamps released in 2005, but the stamp involves is the reprint. The error shows misplace of the perforation due to folding of right top corner of the stamp sheet (one sheet contains 100 stamps). Only one stamp sheet had this problem and the other sheets from the same stack were fine.