《汉书·传·扬雄传下》
从前周朝纲废弛，诸侯纷争，分为十二，合为六七，四分五裂，并为战国。
往者周罔解结，群鹿争逸，离为十二，合为六七，四分五剖，并为战国。
In the past, Zhou Dynasty was decadent, princes were fighting, divided into twelve, combined into six or seven, fragmented, and merged into the Warring States Period.