Hadith 10:185
Abu Bakr narrated to us, he said: Abu Dawud al-Tayalisi narrated to us, from Harun, he said: I asked Ibn Sirin about the divorce of the insane person. He said: "It is nothing. And the authority (Sultan) looks into it; he asks whether he divorced, and he examines his oath."
حدثنا أبو بكر قال حدثنا أبو داود الطيالسي عن هارون قال سألت بن سيرين عن طلاق المجنون فقال ليس بشيء والسلطان ينظر فيه يسأل أنه طلق ويبصر يمينه