Musannaf Ibn Abi Shayba 19:409

Abu Bakr narrated to us, he said: Humayd ibn Abd al-Rahman narrated to us, from Hasan, from Mutarrif, regarding al-Hakam and Amir concerning a slave who has a free wife, and she comes with a child, and he denies him: He said, "He is lashed, and there is no *li'an* (imprecation) between them, and the child is attached to him." And Amir and al-Hakam said regarding a free man who has a slave woman under him, and she came with a child, and he denied him: They said, "There is no *li'an* between them, and the child is attached to him."