Musannaf Ibn Abi Shayba 26:164

Ibn Fudayl narrated to us, from Bassam, from Fudayl, who said: Ibrahim said regarding a woman who left behind her daughter, her son’s daughter, and her mother, and she had no agnatic heir (asaba): For her daughter is three-fifths, for her son’s daughter is one-fifth, and for her mother is one-fifth, according to the judgment of Ali. Abdullah judged regarding it that it is from twenty-four shares: for the son’s daughter from that is the sixth, four shares; for the mother is a quarter of what remains, five shares; and for the daughter is three-quarters of twenty, fifteen shares. Zayd judged regarding it: for the daughter is the half, for the son’s daughter is the sixth, and for the mother is the sixth; and whatever remains is in the public treasury (bayt al-mal) if there is no wala’ (patronage) and no agnatic heir.