Musnad Ahmad 32:1649

'Affan narrated to us, Hammad narrated to us, Thabit and Sulayman al-Taymi narrated to us, from Anas ibn Malik, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "When I was taken on the Night Journey, I passed by Musa while he was standing, praying in his grave at the red sand dune."