Masruq narrates from Sayyiduna Abdullah (may Allah be pleased with him) that he said: "When a man says to his wife: 'Your matter is in your own hands,' or says: 'Decide your matter for yourself,' or hands her over to her family and they accept her, it counts as one irrevocable divorce (ba'in)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9592