Muwatta Malik, 261

Yahya related to me from Malik from Ibn Shihab from Urwa ibn az- Zubayr from A'isha, the wife of the Prophet, may Allah bless him and grant him peace, that the Messenger of Allah, may Allah bless him and grant him peace, used to pray eleven rakas in the night, making them odd by a single one, and when he had finished he lay down on his right side

Aicha, la femme du Prophète (salallahou alayhi wa salam) (Sur lui la grâce et la paix d'Allah) a rapporté que l'Envoyé d'Allah (salallahou alayhi wa salam) r (Sur lui la grâce et la paix d'Allah) faisait la prière nocturne de onze raka'ts dont la dernière était impaire. Une fois, la prière achevée, il se couchait sur le côté droit»