Yahya related to me from Malik from Yahya ibn Said that Said ibn al-Musayyab said, "Abu Bakr as-Siddiq used to pray witr when he wished to go to bed, and Umar ibn al-Khattab used to pray witr at the end of the night. As for me, I pray witr when I go to bed."
أَنَّهُ قَالَ كَانَ أَبُو بَكْرٍ الصِّدِّيقُ إِذَا أَرَادَ أَنْ يَأْتِيَ فِرَاشَهُ أَوْتَرَ وَكَانَ عُمَرُ بْنُ الْخَطَّابِ يُوتِرُ آخِرَ اللَّيْلِ قَالَ سَعِيدُ بْنُ الْمُسَيَّبِ فَأَمَّا أَنَا فَإِذَا جِئْتُ فِرَاشِي أَوْتَرْتُ