@article{AA_2002_14_5_a9,
     author = {P. V. Svetlov},
     title = {Graph-manifolds of nonpositive curvature are virtually fibered over a~circle},
     journal = {Algebra i analiz},
     pages = {188--201},
     publisher = {mathdoc},
     volume = {14},
     number = {5},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_2002_14_5_a9/}
}