[1] The first paper on it may be Shoichi Sakata and Takesi Inoue's two-meson theory of 1942, which also involved two neutrinos.

[2][3] In 1962 Leon M. Lederman, Melvin Schwartz and Jack Steinberger proved the existence of the muon neutrino in an experiment at the Brookhaven National Laboratory.

[5] In September 2011 OPERA researchers reported that muon neutrinos were apparently traveling at faster than light speed.

These results were viewed skeptically by the scientific community at large, and more experiments investigated the phenomenon.

[6] Later, in July 2012, the apparent anomalous super-luminous propagation of neutrinos was traced to a faulty element of the fibre optic timing system in Gran-Sasso.