ψ′ production in Pb–Pb collisions at 158 GeV/nucleon. - Alessandro, B.; Alexa, C.; Arnaldi, R.; Atayan, M.; Beolè, S.; Boldea, V.; Bordalo, P.; Borges, G.; Castor, J.; Chaurand, B.; Cheynis, B.; Chiavassa, E.; et al. (European Physical Journal C -- Particles & Fields, 2007)