Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) continued to recite the qunut of calamity in the Fajr prayer until he departed from this world.
Imam Ahmad recorded it, and Imam al-Bazzar recorded a similar narration; its narrators have been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2835