@article{DAN_1974_214_2_a4,
     author = {A. Ya. Dikovsky},
     title = {On the general notion of complexity of derivation in a context-free grammar},
     journal = {Doklady Akademii Nauk},
     pages = {257--260},
     publisher = {mathdoc},
     volume = {214},
     number = {2},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1974_214_2_a4/}
}