Musannaf Ibn Abi Shayba 1:1071

Hafs ibn Ghiyath narrated to us, from Ash'ath, from al-Hakam and Hammad, from Ibrahim, and from al-Hasan and al-Sha'bi, that they said regarding the one who has wounds, the one afflicted with colic, and the one afflicted with smallpox: He performs tayammum.