@article{TMF_1986_68_2_a9,
     author = {G. M. Zhislin},
     title = {Virtual levels of $n$-particle systems},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {265--275},
     publisher = {mathdoc},
     volume = {68},
     number = {2},
     year = {1986},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1986_68_2_a9/}
}