Sunan an-Nasa'i 2426
سنن النسائي#2426HasanIt was narrated from Abu Dharr:That the Prophet commanded a man to fast on the thirteenth, fourteenth and fifteenth
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahHasan Lighairihi
Al-AlbaniHasan
Zubair Ali ZaiHasan
In-book reference: 22:337