“…The splash of research activity around MPI in recent years [4,5] has been stimulated by the experimental evidence for double parton scattering (DPS) in the processes producing two independently identified hard particles. Such processes have been observed in pp and pp collisions for the final states containing four jets, γ + 3 jets, and W + 2 jets by AFS [6], UA2 [7], CDF [8,9], D0 [10][11][12], AT-LAS [13], and CMS [14] Collaborations. The data on double J/ψ production [15], and single J/ψ production as a function of the event multiplicity [16] can also be successfully interpreted using DPS [17][18][19][20] and MPI models, respectively.…”