Hadithcore
Bulugh al-Maram, 564

Talhah bin ‘AbduIlah bin ‘Auf (RAA) narrated, ‘I offered a funeral prayer led by Ibn ‘Abbas. He recited al-Fatihah and said, ‘You should know that it (reciting al-Fatihah) is a Sunnah of the Prophet (ﷺ).’ Related by Al-Bukhari.

وَعَنْ طَلْحَةَ بْنِ عَبْدِ اَللَّهِ بْنِ عَوْفٍ قَالَ: { صَلَّيْتُ خَلَفَ ابْنِ عَبَّاسٍ عَلَى جَنَازَةٍ, فَقَرَأَ فَاتِحَةَ الكْتِابِ فَقَالَ:

لِتَعْلَمُوا أَنَّهَا سُنَّةٌ

} رَوَاهُ اَلْبُخَارِيُّ [1]‏ .‏

References2 variants
In-Book Reference
Book 3, Hadith 32
English Reference
Book 3, Hadith 588