"Kongcongzi" (Chinese Literature: Collection of debates between Confucius and his descendants) says '4 kin, 鈞, represents 1 koku' and "Enanji" (Chinese Literature from 200 B.C.) says '1 koku consists of 4 kin.'
『孔叢子』に「鈞四謂之石」（4鈞を石という）、『准南子』に「四鈞為一石」（4鈞で1石を為す）とある。