@article{AL_1970_9_4_a6,
     author = {G. P. Kykin},
     title = {Primitive elements of free {Lie} algebras},
     journal = {Algebra i logika},
     pages = {458--472},
     publisher = {mathdoc},
     volume = {9},
     number = {4},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1970_9_4_a6/}
}