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2. F Halzen and A D Martin, Quark and leptons: An introductory course in modern particle physics (John Wiley & Sons, New York, 1984)
3. D Griffiths, Introduction to elementary particles (John Wiley & Sons, New York, 1987)
4. M Arneodo et al, Nucl. Phys. B483, 3 (1997)
5. Y Y Balitsky and L N Lipatov, Sov. J. Nucl. Phys. 28, 822 (1978)