Unitary 4-point correlators from classical geometries Alessandro Bombini, Andrea Galliani, Stefano Giusto, Emanuele Moscato and Rodolfo Russo Eur. Phys. J. C, 78 1 (2018) 8 Published online: 04 January 2018 DOI: 10.1140/epjc/s10052-017-5492-3