With this report, he said, then he performed the two prostrations of forgetfulness after giving the salam.
حدثنا هارون بن عبد الله حدثنا هاشم بن القاسم حدثنا عكرمة بن عمار عن ضمضم بن جوس الهفاني
بهذا الخبر قال ثم سجد سجدتي السهو بعد ما سلم
Sourcing, its chain is hasan. Nasai narrated it in "Sahw," chapter "Salam after the two prostrations of sahw," hadith 1331, from the hadith of Ikrima bin Ammar, and he stated explicitly that he had heard it directly.