《水经注·卷三十六》
寿冷水自城南东流，与卢容水汇合，东注于郎究，究水在下潭积漪成湖，称为郎湖。
寿泠水自城南，东与卢容水合，东注郎究，究水所积，下潭为湖，谓之郎湖浦口。
Shou Leng water flows eastward from the south of the city, converges with Lu Rong water, and flows eastward into Lang Jiu, where Jiu water accumulates in the lower pool to form a lake, known as Lang Lake.