Arabic (Original)
حَدَّثَنَا مُحَمَّدُ بْنُ بِشْرٍ حَدَّثَنَا عُبَيْدُ اللَّهِ عَنْ نَافِعٍ عَنِ ابْنِ عُمَرَ قَالَ وَمَنْ صَلَّى مِنْ أَوَّلِ اللَّيْلِ فَلْيَجْعَلْ آخِرَ صَلَاتِهِ وِتْرًا فَإِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كَانَ يَأْمُرُ بِذَلِكَ.
English Translation
Muhammad ibn Bishr narrated to us: Ubaydullah narrated to us, from Nafi', from Ibn Umar, who said: Whoever prays during the first part of the night, let him make the last of his prayer witr, for the Messenger of Allah, peace and blessings be upon him, used to command that.