Sunan an-Nasa'i 3515
سنن النسائي#3515SahihAbu Salamah bin 'Abdur-Rahman said:"Ibn 'Abbas, Abu Hurairah and I were together, and Ibn 'Abbas said: 'If a woman gives birth after her husband dies, her 'Iddah is the longer of the two periods.'" Abu Salamah said: "We sent Kuraib to Umm Salamah to ask her about that. He came to us and told us from her that the husband of Subai'ah died and she gave birth a few days after her husband died, and the Messenger of Allah told her to get married
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: 27:127