@article{AA_1997_9_6_a7,
     author = {A. B. Pushnitskii},
     title = {A representation for the spectral shift function in the case of perturbations of fixed sign},
     journal = {Algebra i analiz},
     pages = {197--213},
     publisher = {mathdoc},
     volume = {9},
     number = {6},
     year = {1997},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_1997_9_6_a7/}
}