Inclusive J/ψ photoproduction and polarization at HERA in the k T -factorization approachS.P. Baranov, A.V. Lipatov and N.P. ZotovEur. Phys. J. C, 71 4 (2011) 1631DOI: https://doi.org/10.1140/epjc/s10052-011-1631-4