Infrared-improved soft-wall AdS/QCD model for mesons Ling-Xiao Cui, Zhen Fang and Yue-Liang Wu Eur. Phys. J. C, 76 1 (2016) 22 Published online: 19 January 2016 DOI: 10.1140/epjc/s10052-015-3866-y