Musannaf Ibn Abi Shayba 1:789

789. Khalid ibn Hayyan narrated to us, from Ja'far ibn Burqan, who said: I said to al-Zuhri, "I perform ghusl (ritual bath) for janaba (major ritual impurity), and some of the water from my washing splashes into my vessel." He said, "There is no harm in it."