@article{10_4153_CJM_2005_053_9,
     author = {Zhitomirskii, M.},
     title = {Relative {Darboux} {Theorem} for {Singular} {Manifolds} and {Local} {Contact} {Algebra}},
     journal = {Canadian journal of mathematics},
     pages = {1314--1340},
     year = {2005},
     volume = {57},
     number = {6},
     doi = {10.4153/CJM-2005-053-9},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2005-053-9/}
}