It was narrated that Ibn 'Umar said:

"Whoever prays during the night, let him make the last of his prayers at night witr, because the Messenger of Allah ﷺ used to enjoin that."

أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ نَافِعٍ، أَنَّ ابْنَ عُمَرَ، قَالَ مَنْ صَلَّى مِنَ اللَّيْلِ فَلْيَجْعَلْ آخِرَ صَلاَتِهِ وَتْرًا فَإِنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَأْمُرُ بِذَلِكَ .