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The production of J/ψJ/ψ, J/ψψ production have been measured in 4μ final state in pp collisions at a mass center energy sqrt(s) = 8 GeV using data collected by the CMS experiment at the LHC. The data sample corresponds to an integrated luminosity of 18.0 fb-1 . J/ψψ signal is observed for the first time. The 4d fit is used to separate prompt double quarkonia from non-prompt double quarkonia.