《宋书·志·卷十三》
又在年数之下是十一个月，评论中说成是九个月，有关的数字经常出现差错都是类似的情况。
又年数之余有十一月，而议云九月，涉数每乖，皆此类也。
There are eleven months under the year again. The comments say that it is nine months. Similar situations often occur in related numbers.