Cygnus X-3 at high energies: A critical review

The standard model would be endangered if deep-underground observations of muons coming from Cygnus X-3 were confirmed. The detection of cosmic radiation at high energies from Cygnus X-3 would also have far reaching implications in astrophysics. We review the underground and surface experiments and question the consistency of the reported observations. We propose some experimental and statistical tests to settle this important question