The 10th-century treatise "De Administrando Imperio" ("On the management of the Empire", later "DAI"), written in Greek by Constantine VII Porphyrogennetos, is the only known document that suggests "White Croatia" as the place from which Croats migrated to Dalmatia, bordering the coastline of the Adriatic Sea. In Chapter 30, under the heading "The Story of the Province of Dalmatia," it says that "the Croats at that time were dwelling beyond Bagibareia, where the Belocroats are now... The rest of the Croats stayed over near Francia, and are now called the Belocroats, that is, the White Croats, and have their own archon; they are subject to Otto, the great king of Francia, which is also Saxony, and are unbaptized, and intermarry and are friendly with the Turks".