1. Scientific and Technical Research Center, MJIB; P.O. Box 3562, Taipei, TW, R.O.C.
2. Institute of Graphic Arts, Chinese Culture University; Yang-ming-shan, Taipei, TW, R.O.C.
3. Questioned documents examiner Investigation Bureau, Ministry of Justice P.O. Box 3562 Taipei County TW, R.O.C.
4. Institute of Optical Sciences, National Central University; Chung-Li TW, R.O.C.