  Structures in invariant mass distributions from (mu,pi) combinations in the
range 0.380<mupi<0.470 GeV from neutrino and kaon experiments are presented in
comparable formats. No artifacts have been found to account for any part of the
structure. Hypotheses that the similarities are due to recurrent statistical
fluctuations are beyond credibility. My conclusion is that the similarities are
overwhelming evidence that the structure is of an unexplained physical origin.
It includes an enhancement which would accord with the decay of a narrow
(mu,pi) state of mass 0.429 GeV. The purpose of this report is to request and
enable every experimenter with precise mupi distributions to investigate their
degree of correspondence with these analyses.
