Sunan Abi Dawud 1351

Narrated 'Aishah: The Messenger of Allah (ﷺ) used to observe the witr prayer with nine rak'ahs. Then he used to pray seven rak'ahs (of witr prayer). He would pray two rak'ahs sitting after the witr in which he would recite the Qur'an (sitting). When he wished to bow, he stood up and bowed and prostrated. Abu Dawud said: These two traditions have been transmitted by Khalid b. 'Abd Allah al-Wasiti. In his version he said: 'Alqamah b. Waqqas said: O mother, how did he pray the two rak'ahs ? He narrated the rest of the tradition to the same effect