Musnad Ahmad 32:1174

Yazid narrated to us, Hammad bin Zaid informed us, Thabit al-Bunani narrated to us, Anas said: "When we buried the Messenger of Allah, may Allah bless him and grant him peace, and returned, Fatimah said: 'O Anas, did your souls find it acceptable to bury the Messenger of Allah, may Allah bless him and grant him peace, in the earth and return?'"