Musnad Abu Ya'la al-Mawsili 105:39

Khalf ibn Hisham narrated to us, he said: Abu al-Ahwas narrated to us, from Abu Ishaq, from Najiyah, who said: Ammar said: I became in a state of major ritual impurity (janabah) while I was among the camels, and I did not find water. So I rolled in the dust just as an animal rolls. Then I came to the Messenger of Allah, peace and blessings of Allah be upon him, and informed him of that. He said: "It would have been sufficient for you to perform tayammum instead of that."