Musannaf Ibn Abi Shayba 1:1659

Abu Bakr narrated to us, he said: Abu al-Ahwas narrated to us, from Abu Ishaq, from Najiyah Abu Khuffaf, from Ammar, who said: I became in a state of major ritual impurity (janabah) while I was with the camels, and I did not find water, so I rolled in the dust as an animal rolls. Then I came to the Messenger of Allah, may Allah bless him and grant him peace, and informed him. He said: "It is sufficient for you regarding that to perform tayammum."