Hadith No: 18
Ibn Abi Asim - al-Sunnah - Chapter on the Mentioned Virtues of Ali (peace be upon him)
Volume: (2) Page Number: (602/603)
[The text is lengthy, so only the relevant excerpt is provided here]
1351 - Muhammad ibn al-Muthanna narrated to us, saying: Yahya ibn Hammad narrated to us, saying: Abu 'Awanca narrated to us, from Yahya ibn Sulaym, known as Abu Balj, from Amr ibn Maymun
from Ibn Abbas .... who said: "And he was the first to embrace Islam among people after Khadijah." He continued: "And he sacrificed himself, wearing the Prophet's (peace be upon him and his holy progeny) robe and sleeping in his place ...."