@Article{         Maslova,
  Author        = "Maslov, A.",
  date-added    = "2013-12-10 14:22:08 +0000",
  date-modified = "2013-12-10 14:25:44 +0000",
  Journal       = "Soviet. Math. Doklady",
  Keywords      = "indexed grammars",
  Number        = "15",
  Pages         = "1170--1174",
  Title         = "The hierarchy of indexed languages of an arbitrary level",
  Year          = "1974"
}

@Article{ Maslova, Author = "Maslov, A.", date-added = "2013-12-10 14:22:08 +0000", date-modified = "2013-12-10 14:25:44 +0000", Journal = "Soviet. Math. Doklady", Keywords = "indexed grammars", Number = "15", Pages = "1170--1174", Title = "The hierarchy of indexed languages of an arbitrary level", Year = "1974" }