Jami` at-Tirmidhi 738
جامع الترمذي#738SahihAbu Hurairah narrated that :the Messenger of Allah said: "When a half of Sha'ban remains then do not fast
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Bashar Awad MaaroufHasan Sahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 8:57