1. Fermilab Lattice, MILC collaboration, D. Mohler, A.S. Kronfeld, J.N. Simone, C. DeTar, S.-h. Lee and L. Levkova, Low lying charmonium states at the physical point, PoS(LATTICE2014)085 [ arXiv:1412.1057 ] [ INSPIRE ].
2. B.A. Galloway, P. Knecht, J. Koponen, C.T.H. Davies and G.P. Lepage, Radial and orbital excitation energies of charmonium, PoS(LATTICE2014)092 [ arXiv:1411.1318 ] [ INSPIRE ].
3. D. Becirevic, M. Kruse and F. Sanfilippo, Lattice QCD estimate of the η c (2S) → J/ψγ decay rate, JHEP 05 (2015) 014 [ arXiv:1411.6426 ] [ INSPIRE ].
4. G.C. Donald et al., Precision tests of the J/ψ from full lattice QCD: mass, leptonic width and radiative decay rate to η c , Phys. Rev. D 86 (2012) 094501 [ arXiv:1208.2855 ] [ INSPIRE ].
5. N. Brambilla et al., QCD and Strongly Coupled Gauge Theories: Challenges and Perspectives, Eur. Phys. J. C 74 (2014) 2981 [ arXiv:1404.3723 ] [ INSPIRE ].