@article{MZM_2001_69_4_a4,
     author = {A. O. Ivanov and A. A. Tuzhilin and L\^e H\^ong V\^an},
     title = {Nontrivial {Critical} {Networks.} {Singularities} of {Lagrangians} and a {Criterion} for {Criticality}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {566--580},
     publisher = {mathdoc},
     volume = {69},
     number = {4},
     year = {2001},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2001_69_4_a4/}
}