%0 Journal Article %A V. F. Los' %T Projection operator method in the theory of disordered systems. I.~Spectra of quasiparticles %J Teoretičeskaâ i matematičeskaâ fizika %D 1987 %P 85-102 %V 73 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/TMF_1987_73_1_a8/ %G ru %F TMF_1987_73_1_a8