RT Article T1 "Half-Nomads" on the Middle Euphrates and the Concept of Dimorphic Society JF Altorientalische Forschungen VO 24 IS 1 SP 44 OP 48 A1 Liverani, Mario LA German PB De Gruyter YR 1997 UL https://www.ixtheo.de/Record/180147057X DO 10.1524/aofo.1997.24.1.44