Musannaf Ibn Abi Shayba 3:3603

Ubaydah ibn Humayd narrated to us, from Dawud ibn Abi Hind, from al-Nu’man ibn Salim, from ‘Amr ibn Aws, from ‘Anbasah ibn Abi Sufyan, from Umm Habibah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever prays twelve prostrations (rak'ahs) in a day voluntarily, a house will be built for him in Paradise."