Neutrino Data and Neutrino-Antineutrino Transition
  A problem, whether a neutrino-antineutrino transition could be responsible for the muon neutrino deficit found in underground experiments (Super-Kamiokande, MACRO, Soudan 2) and in the accelerator long-baseline K2K experiment, is discussed in this paper. The intention of the work is not consideration of concrete models for muon neutrino-antineutrino transition but a desire to attract an attention to another possibility of understanding the nature of the measured muon neutrino deficit in neutrino experiments. 
E.N.Alexeyev and L.V.Volkova (Institute for Nuclear Research of   Russian Academy of Sciences)