Sunan an-Nasa'i 528
سنن النسائي#528SahihIt was narrated that An-Nu'man bin Bashir said:"I am the most knowledgeable of people about the time of the 'Isha' prayer. The Prophet (ﷺ) used to pray it when the moon set on the third night of the month
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 ZaiSahih
In-book reference: 6:35