《宋史·志·卷三》
罗堰三颗星，在牵牛星柬面，是战具拒马，主管堤防塘堰，堵住蓄积水源，用来灌溉。
罗堰三星，在牵牛东，拒马也，主堤塘，壅蓄水源以灌溉也。
The three stars of Luo Yan, on the negative face of the Altair star, are rejection horses of the war equipment, in charge of the embankments and dams, blocking the accumulation of water sources, and used for irrigation.