Complex sentence: According to Bialeková and other archaeologists, the axe-shaped ingots unearthed in great number in fortresses served as "premonetary currencies", but their theory has not universally accepted, because these objects have also been interpreted as "intermediate products intended for further treatment".
Split into simpler sentences: According to Bialeková and other archaeologists, the axe-shaped ingots unearthed in great number in fortresses served as "premonetary currencies". This theory has not universally been accepted, because these objects have also been interpreted as "intermediate products intended for further treatment".