Musannaf Ibn Abi Shayba 1:1040

'Abbad ibn al-'Awwam narrated to us, from Sa'id, from Qatadah, from Sa'id ibn al-Musayyib and al-Hasan: That they used to see no harm if a man was on a journey and did not have water with him, that he should have intercourse with his wife, then perform tayammum.