A phenomenological theory of phase transitions in high T_{c}   superconductors
  A phenomenological theory is suggested to explain the experimentally discovered "paramagnetic peculiarity" and the unconventional change of the energetic state of a layers of high T_{c} of Y-Ba-Cu-O in the vicinity of the phase transition. The physical conditions are found under which these peculiarities are revealed. It is shown that the suggested theory qualitatively describes the experimental data. 
D.M.Sedrakian