《元史·列传·卷十二》
真定的富豪人家放高利贷，虽不过期也要加倍取息。布鲁海牙将他们治罪，使债务人付息不超过本钱，定为制度。
真定富民出钱贷人者，不逾时倍取其息，布鲁海牙正其罪，使偿者息如本而止，后定为令。
The rich families in Zhending gave out usurious loans, and doubled the interest owed even if it was not yet due. Buluhaiya convicted them, so that debtors only paid interest that did not exceed the principal, which became a rule.