《宋史·列传·卷一百七十一》
七月七日，武仙的爱将刘仪率领二百名壮士投降，孟珙问武仙的虚实情况，刘仪说 ：武仙所据的九寨，最大的是石穴山寨，马蹬、沙窝、岵山三寨挡在它的前面；这三寨不攻破，石穴山寨也难攻破。
七月己酉，仙爱将刘仪领壮士二百降，珙问仙虚实，仪陈： 仙所据九砦，其大砦石穴山，以马蹬、沙窝、岵山三砦蔽其前；三砦不破，石穴未易图也。
On July 7th, Wuxian's favorite general Liu Yi led two hundred warriors to surrender. Meng Gong asked about Wuxian's real situation. Liu Yi said: The nine fortresses where Wuxian is located, the largest is the Shixue Mountain Fortress; Madeng, Shawo, and Cishan Fortresses block in front of it; if these three fortresses are not breached, the Shixue Mountain Fortress will be difficult to breach.