Reference Library - Electron Microscopy
Najjar, A.H. "Great Britiain: The 1858-1879 1d Rose-Red Plate 77", The Collectors Club Philatelist, Vol. 88, No. 2, September-October 2008, pp. 269-284.
White, R.H. "Application of Electron Microscope and X-Ray Analyses to Identification Techniques for Stamps and Proof Papers", The United States Specialist, Parts I, II and III, Vol. 60, Nos. 4, 6 and 8. pp. 187-191, 299-305, 419-427.