Sunan Abi Dawud 2335
سنن أبي داود#2335SahihNarrated Abu Hurairah:The Messenger of Allah (ﷺ) as saying: Do not fast one day or two days just before Ramadan, except in the case of a man who has been in the habit of observing the particular fast, for he may fast on that day
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih Bukhari (1914) Sahih Muslim (1082)
In-book reference: 14:23