  A study of Z-boson pair production in e+e- annihilation at center-of-mass
energies between 190 GeV and 209 GeV is reported. Final states containing only
leptons, (l+l-l+l- and l+l-nn), quark and lepton pairs, (qql+l-, qqnn) and only
hadrons (qqqq) are considered. In all states with at least one Z boson decaying
hadronically, lifetime, lepton and event-shape tags are used to separate bb
pairs from qq final state. Limits on anomalous ZZgamma and ZZZ couplings are
derived from the measured cross sections and from event kinematics using an
optimal observable method. Limits on low scale gravity with large dimensions
are derived from the cross sections and their dependence on polar angle.
