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2. C.A. Wunderlich, On the temperature in diseases, A Manual of Medical Thermometry. Translated from the second German edition by W. Bathurst Woodman. The New Sydenham Society, London 1871.
3. Thermographic techniques with liquid crystals in medicine;Flesch,1984
4. Human Body Temperature its Measurement and Regulation;Houdas,1982
5. The discovery of infrared radiation in 1800;Ring;Imaging Science Journal,2000