《后汉书·列传·班彪列传上》
春秋之后，七国纷争，秦国吞并诸侯，就有《战国策》三十三篇问世。
春秋之后，七国并争，秦并诸侯，则有《战国策》三十三篇。
After the Spring and Autumn period, the seven states fought for hegemony, and the Qin state annexed the feudal states, and the "Warring States Policy" of thirty-three chapters was published.