Muwatta Malik Book 6, Hadith 5
Yahya related to me from Malik that Yazid ibn Ruman said, "The
people used to watch the night in prayer during Ramadan for twenty-
three rakas in the time of Umar ibn al-Khattab."
Yahya related to me from Malik from Muhammad ibn Yusuf that as- Sa'ib ibn Yazid said, "Umar ibn al-Khattab ordered Ubayy ibn Kab and Tamim ad-Dari to watch the night in prayer with the people for eleven rakas.The reciterof the Qur'an would recite the Mi'in (a group of medium-sized suras) until we would be leaning on our staffs from having stood so long in prayer. And we would not leave until the approach of dawn."
Yahya related to me from Malik from Da'ud ibn al-Husayn that he heard al-Araj say, "I never saw the people in Ramadan, but that they were cursing the disbelievers." He added, "The reciter of Qur'an used to recite surat al-Baqara in eight rakas and if he did it in twelve rakas the people would think that he had made it easy."