Talha bin Abdullah bin Awf narrates that I offered the funeral prayer behind Ibn Abbas (may Allah be pleased with him), and he recited Surah Al-Fatihah. When he finished with salam, I inquired about it, and he replied: "It is Sunnah and the truth."
Hadith Referenceمسند الإمام الشافعي / كتاب الجنائز / 586
Hadith Takhrijاخرجه البخاري، الجنائز، باب قراءة فاتحة الكتاب على الجنازة (1335)۔