While Abu Salama and I were with Ibn Abbas, a woman came to him and said that her husband had died while she was pregnant, and she had given birth less than four months after the day he died.Ibn Abbas said, "Her waiting period is the longer of the two terms."Abu Salama said, "A man from among the companions of the Prophet ﷺ told me that Sabia al-Aslamiyya came to the Messenger of Allah ﷺ and told him that her husband had died while she was pregnant, and she had given birth less than four months later. The Messenger of Allah ﷺ instructed her that she could marry."Abu Hurairah said, "And I bear witness to that."
أخبرنا إسحق بن إبراهيم قال أنبأنا عبد الرزاق قال أنبأنا ابن جريج قال أخبرني داود بن أبي عاصم أن
بينما أنا وأبو هريرة عند ابن عباس إذ جاءته امرأة فقالت توفي عنها زوجها وهي حامل فولدت لأدنى من أربعة أشهر من يوم مات فقال ابن عباس آخر الأجلين فقال أبو سلمة أخبرني رجل من أصحاب النبي ﷺ أن سبيعة الأسلمية جاءت إلى رسول الله ﷺ فقالت توفي عنها زوجها وهي حامل فولدت لأدنى من أربعة أشهر فأمرها رسول الله ﷺ أن تتزوج قال أبو هريرة وأنا أشهد على ذلك
[Its isnad is sahih] and it is found in Al-Kubra, hadith no. 5711.