Musannaf Ibn Abi Shayba 1:1338

1338. Isma'il ibn 'Ayyash narrated to us, from 'Abd al-'Aziz ibn 'Ubayd Allah, who said: I heard al-Harith al-'Ukli saying regarding a man who spits and there is blood in his spittle: He said: If the blood overcomes the spittle, then in it is wudu (ablution).