Sunan an-Nasa'i 2353
سنن النسائي#2353SahihIt was narrated from Umm Salamah:That the Prophet would not fast any month of the year in full except Shaban and he used to join it to Ramadan
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiHasan
In-book reference: 22:264