@article{DM_1989_1_2_a4,
     author = {M. Yu. Baryshev},
     title = {Approximations of words by words without self-duplication},
     journal = {Diskretnaya Matematika},
     pages = {52--56},
     publisher = {mathdoc},
     volume = {1},
     number = {2},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1989_1_2_a4/}
}