  The neutrino oscillations probabilities depend on mass squared differences;
in the case of 3-neutrino mixing, there are two independent differences, which
have been measured experimentally. In order to calculate the absolute masses of
neutrinos, we have conjectured a third relation, in the form of a sum of
squared masses. The calculated masses look plausible and are in good agreement
with the upper bounds coming from astrophysics.
