Around 20 AD, Strabo wrote the "Geographica" that provides information regarding the extent of regions inhabited by the Dacians. On its basis, Lengyel and Radan (1980), Hoddinott (1981) and Mountain (1998) consider that the Geto-Dacians inhabited both sides of the Tisza river before the rise of the Celtic Boii and again after the latter were defeated by the Dacians. The hold of the Dacians between the Danube and the Tisza appears to have been tenuous. However, the Hungarian archaeologist Parducz (1856) argued for a Dacian presence west of the Tisza dating from the time of Burebista. According to Tacitus (AD 56 – AD 117) Dacians were bordering Germany in the south-east while Sarmatians bordered it in the east.