Bose-Einstein Correlations in W+W- events at LEP2
  Bose-Einstein correlations (BEC) between final state particles in the reaction e+e- -> W+W- -> q_1 anti-q_2 q_3 anti-q_4 have been studied. Data corresponding to a total integrated luminosity of 550 pb^{-1}, recorded by the DELPHI detector at centre-of-mass energies ranging from 189 to 209 GeV, were analysed. An indication for inter-W BEC between like-sign particles has been found at the level of 2.4 standard deviations of the combined statistical and systematic uncertainties. 
The DELPHI Collaboration, J. Abdallah, et al