Maliks Muwatta Book 2, Hadith Number 18.

Section : Things which do not break Wudu.

Yahya related to me from Malik from Nafi that Abdullah ibn Umar prepared the body of one of Said ibn Zayd’s sons for burial and carried it and then entered the mosque and prayed without doing wudu.

Yahya said that Malik was asked whether it was necessary to do wudu because of regurgitating undigested food and he said, “No, wudu is not necessary, but the mouth should be rinsed.”