Musannaf Ibn Abi Shayba 26:47

Abu Khalid al-Ahmar narrated to us, from Hajjaj, from Abu Qays, from Hudhayl, from Abdullah, who said: The Messenger of Allah (may Allah bless him and grant him peace) gave a ruling regarding a daughter, a son’s daughter, and a sister. He gave the daughter one-half, the son’s daughter one-sixth to complete the two-thirds, and the sister what remained. Abu Bakr said: This is out of six shares; for the daughter are three shares, for the son’s daughter is one share, and for the sister are two shares.