Using HERA data to determine the infrared behaviour of the BFKL amplitude H. Kowalski, L.N. Lipatov, D.A. Ross and G. Watt Eur. Phys. J. C, 70 4 (2010) 983-998 Published online: 18 November 2010 DOI: 10.1140/epjc/s10052-010-1500-6