《徐霞客游记·浙游日记下》
下了岭是钮坑，也有几十家居民住着，又翻越一座山岭，叫思山祠岭，它是北山后支向南延伸而下的第四层、距离玲珑岩西面又约有六里了。
下岭为钮坑，亦有居人数十家。又逾一岭曰思山祠，则北山后支南下之第四层也，去玲珑岩西又约六里矣。
Down the ridge is Niu Keng, where dozens of residents also live. After crossing another ridge called Sishan Ci Ling, it is the fourth layer of the north mountain branches extending southward, and it is about six more li from the west of Linglongyan.