See this paper or this paper. This result can be also proven using the arguments of Eleanor Rieffel here which avoid asymptotic cones (in the case you do not accept the Axiom of Choice).

See Kapovich and Leeb On asymptotic cones and quasi-isometry classes of fundamental groups of 3-manifolds, or Kapovich, Kleiner and Leeb Quasi-isometries and the de Rham decomposition. This result can be also proven using the arguments of Eleanor Rieffel in Groups quasi-isometric to $H^2\times R$ (Journal of the London Mathematical Society 64 Issue 1 (2001) 44–60 doi:10.1017/S0024610701002034) which avoid asymptotic cones (in the case you do not accept the Axiom of Choice).