p. 410 ^ Bossert, Helmut T., Asia , Istanbul, 1946. ^ ANCIENT SILK ROAD TRAVELLERS ^ National Geographic Atlas of the World (7th ed.). Washington, DC: National Geographic . 1999. ISBN   978-0-7922-7528-2 .   "Europe" (pp. 68–9); "Asia" (pp. 90–1): "A commonly accepted division between Asia and Europe is formed by the