I. Denysenko, D. Ambrose, A. Amoroso et al.|Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields|2015
M. Ablikim, L. Fava, M. N. Achasov et al.|Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields|2013