@article{MAN_1962__146_160934,
     author = {K.-T. CHEN},
     title = {Decomposition of {Differential} {Equations.}},
     journal = {Mathematische Annalen},
     pages = {263--278},
     publisher = {mathdoc},
     volume = {146},
     year = {1962},
     zbl = {0166.02802},
     url = {http://geodesic.mathdoc.fr/item/MAN_1962__146_160934/}
}