Musannaf Ibn Abi Shaybah

Hazrat Ash'ath narrates that Hasan Basri said: When a man accuses his wife by naming another man, the punishment of qazf (false accusation of adultery) will be imposed on him. And Hazrat Ibn Sirin said: The punishment will not be imposed on him. The Holy Prophet (peace and blessings be upon him) made such a person perform li'an who had accused his wife of adultery with Ibn Sahma.

Hazrat Muhammad bin Salim narrates that Hazrat Sha’bi said: When a man accuses his wife by naming someone, then only one punishment will be applied to him on account of both of them. He said: Whichever of the two takes hold of it for their punishment, the other will not have the right to the punishment. If the woman initiates, she will perform li’an with her husband and will not be flogged because of the man, and if she is flogged because of the man, then there will be no li’an with the woman.