《明史·志·卷七》
崇祯年间，朝廷议论采用西洋新历，皇上命令阁臣徐光启、光禄卿李天经先后管理此事，编成《历书》一百三十多卷，多能提出古人所没能提出的看法。
崇祯中，议用西洋新法，命阁臣徐光启、光禄卿李天经先后董其事，成《历书》一百三十馀卷，多发古人所未发。
During the Chongzhen period, the court discussed using the new Western calendar, and the emperor ordered the Grand Secretariat Xu Guangqi and the Light Graceful Gentleman Li Tianjing to manage the matter and compile "The Book of the Calendar" in more than 130 volumes, which mostly put forward ideas that the ancients had failed to put forward.