Probing unparticle theory via lepton-flavor violating process J/ψ→ll′ at BESIII Zheng-Tao Wei, Ye Xu and Xue-Qian Li Eur. Phys. J. C, 62 3 (2009) 593-598 Published online: 03 June 2009 DOI: 10.1140/epjc/s10052-009-1071-6