@article{TMF_2012_171_2_a13,
     author = {H. Frahm and J. H. Grelik and A. Seel},
     title = {Persistent currents in open spin chains},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {340--352},
     publisher = {mathdoc},
     volume = {171},
     number = {2},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_2012_171_2_a13/}
}