《资治通鉴·魏纪·魏纪九》
他们从南安、陇西进军可以就地食用羌人的粮食，如果向祁山进军，那里成熟的麦子有千顷之多，足以成为他们的外部粮仓，这是五。
从南安、陇西因食羌谷，若趣祁山，熟麦千顷，为之外仓，五也。
They can get provisions from the Qiangs in Nanan and Longxi if they advance to Qishan, there will be thousands of acres of ripe wheat, which can be used as their external granary, this is the fifth point.