Musannaf Ibn Abi Shaybah

Hajjaj narrates from a shaykh, from Muhammad bin Hanafiyyah, that in the case where both wife and parents are heirs, the wife will be given one-fourth and the mother will be given one-third of the remainder. Abu Bakr says that this will be out of four shares: one share for the wife, that is, one-fourth, and one-third of the remainder for the mother, which will also be one share, and two shares for the father.