Musannaf Ibn Abi Shaybah

Sha'bi narrates that regarding the son of a woman who performed li'an, who dies leaving his mother and a maternal brother, Hazrat Ali (may Allah be pleased with him) said that his mother should be given one-third of the wealth, and his brother should be given one-sixth of the wealth, and the remaining wealth should also be returned to them according to the method of "radd", thus their share will become two-thirds and one-third. And Hazrat Ibn Mas'ud (may Allah be pleased with him) used to say that the mother should be given one-third of the wealth and the brother one-sixth of the wealth, and the remaining wealth should be returned to the mother. Hazrat Abu Bakr said that this issue should be calculated from six shares according to the statements of all the companions.