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2. J.E. Dohany and L.E. Robb in Kirk-Othmer: Encyclopedia of Chemical Technology, Volume II, 3rd Ed., 1980 by John Wiley & Sons, Inc.
3. A.J. Lovinger, Science, 220, 1115 (1983)
4. in Developments in Crystalline Polymers, D.C. Bassett, Ed., Applied Science, London 1982, Vol. 1, 195 (Chapter 5).