We investigate the CMS potential for the observation and study of the {p}{p}\to {Z⁰}{Z⁰}\to {e⁺e^-}{e⁺e^-} and {p}{p}\to W{Z⁰}\to 3\ell \ (\ell =e,\mu ) reactions, using fully simulated signal and background samples. It is shown that these processes are potentially accessible with early CMS data, thanks to relatively high production cross sections at LHC energies, together with clear signatures of the multi-lepton final states. The main systematic effects relevant for cross section measurements with 1 and 10 fb^-1 of data are addressed. We demonstrate that multiple gauge-boson production in {p}{p} collisions at LHC energies can be observed in the early phase of the experiment, with an integrated luminosity of 1 fb^-1 or less.

PACS numbers: 13.38.--b, 13.90.+i