Constraints on unparticle interactions from particle and antiparticle oscillations Shao-Long Chen, Xiao-Gang He, Xue-Qian Li, Ho-Chin Tsai and Zheng-Tao Wei Eur. Phys. J. C, 59 4 (2009) 899-906 Published online: 09 January 2009 DOI: 10.1140/epjc/s10052-008-0823-z