1. Bobbitt, J. M. (1963) Thin Layer Chromatography. Reinhold Pub. Co. New York.
2. Brand, J. C. D. and Eglinton, G. (1965) Applications of Spectroscopy. 234 pp. Oldbourne Press, London.
3. Burchfield, H. P. and Storrs, E. E. (1962) Biochemical Application of Gas Chromatography. Academic Press, New York.
4. Carr, D. J. ed. (1972) Plant Growth Substances, 1970. 837 pp. Springer Verlag, Berlin.
5. Cross, A. D. and Jones, R. A. (1969) An Introduction to Practical IR Spectroscopy. 3rd edn. Butterworths, London.