Photon-photon interactions have been studied at the ?-factory DAΦNE with the detector KLOE operating the machine at GeV, without tagging of the final leptons. The results about the γγ → η process and the evidence for γγ → π~(0)π~(0) production at low π~(0)π~(0) invariant mass are reviewed. The process γγ → π~(0) will be studied at KLOE-2 running the machine at ?-peak thanks to new lepton tagger detectors. In particular, the possibility to measure the two-photon width of π~(0) and the π~(0)γ*γ transition form factor in the low (space-like) Q~(2) region is considered.
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