Musannaf Ibn Abi Shaybah 33782 — Those who permitted giving wala

Sa'id narrated from Qatadah, and in another place I found this narration from Sa'id bin al-Musayyib, that he saw no harm in selling wala' when it arose from a contract of manumission (mukatabah), and he disliked it when it arose from an outright emancipation.