\documentclass[12pt]{article}
\usepackage{amsmath,amssymb,amsfonts}
\begin{document}
Discovery of the CP-violation in the lepton sector is one of the
main challenges of the particle physics. We search for possible
principles, symmetries and phenomenological relations, which
could lead to particular values of the CP-violating Dirac phase,
$\delta$. In this connection
we discuss two extreme cases ($\delta =
0$, and the maximal CP-violation, $\delta = \pm \pi/2$) and relate
them to the peculiar pattern of neutrino mixing. The maximal
CP-violation can be related to the $\nu_\mu - \nu_\tau$
reflection symmetry. In this paper, we study various aspects of
this symmetry and introduce a generalized reflection symmetry that
can lead to an arbitrary phase depending on the parameter of the
symmetry transformation. We find that the generalized reflection
symmetry predicts a simple relation between the Dirac and Majorana
phases. We also consider the possibility of certain relations
between the CP-violating phases in the quark and lepton sectors.
\end{document}