Musannaf Ibn Abi Shayba 9:1131

Waki’ narrated to us, from ‘Abd al-Rahman, from Ibn ‘Abis, who said: I heard Ibn ‘Abbas being asked about the nursing woman who breastfeeds a child one suckling. He said: "If the child is satisfied [by it], it makes forbidden for him [the woman] and whatever she has given birth to."