Musnad Ahmad 1153:324

'Abdah ibn Sulayman narrated to us, he said: Muhammad ibn Ishaq narrated to us, from Fatimah bint Muhammad, from 'Amrah, from 'Aishah, who said: "We did not know of the burial of the Messenger of Allah (may Allah bless him and grant him peace) until we heard the sound of the shovels at the end of the night, on the night of Wednesday." Muhammad said: "And the *masahi* (shovels) are the *murur* (spades)."