1. R. Huber, An interim report on the application of the microscope photometer to document examination (unpublished paper presented at the 1966 Meeting of the American Society of Questioned Document Examiners).
2. A. Cole, The measurement and designation of colour (unpublished paper presented at the 1966 Meeting of the American Society of Questioned Document Examiners).
3. The examination of colour;Cole;J. Forensic Sci.,1973
4. An evaluation of the Nanometrics Incorporated microspectrophotometer the ‘Nanospec 10 S’;Beatti;HOCRE Report No 306,1979
5. D.L. Mauzey, Evaluation of the Nanometrics 10 microspectrophotometer and the LEITZ Ultropak (unpublished paper 1980).