Asturian has several dialects. Regulated by the Academia de la Llingua Asturiana, it is mainly spoken in Asturias (except in the west, where Galician-Asturian is spoken). The dialect spoken in the adjoining area of Castile and León is known as Leonese. Asturian is traditionally divided into three dialectal areas, sharing traits with the dialect spoken in León: western, central and eastern. The dialects are mutually intelligible. Central Asturian, with the most speakers (more than 80 percent) is the basis for standard Asturian. The first Asturian grammar was published in 1998, and the first dictionary in 2000.