Abu Salamah bin Abd al-Rahman narrates from Sayyidah Aishah (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) used to pray thirteen rak'ahs at night; he (peace and blessings be upon him) prayed nine witr, or as he said, and he (peace and blessings be upon him) prayed two rak'ahs sitting; then he offered two rak'ahs between the adhan and the iqamah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4820