@article{DM_1989_1_4_a1,
     author = {Z. R. Dang},
     title = {Upper bounds on finite-automaton complexity for generalized regular expressions in a~one-letter alphabet},
     journal = {Diskretnaya Matematika},
     pages = {12--16},
     publisher = {mathdoc},
     volume = {1},
     number = {4},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1989_1_4_a1/}
}