I asked Ibn Abbas about the witr prayer, and he said, "I heard the Messenger of Allah ﷺ say, 'A single rakah at the end of the night.'"Then I asked Ibn Umar, and he said, "I heard the Messenger of Allah ﷺ say, 'A single rakah at the end of the night.'"
حدثنا عبد الصمد حدثنا همام حدثنا قتادة
سألت ابن عباس عن الوتر فقال سمعت رسول الله ﷺ يقول ركعة من آخر الليل وسألت ابن عمر فقال سمعت رسول الله ﷺ يقول ركعة من آخر الليل
Its isnad is sahih. Abu Majliz, with the mim vowelled kasra, the jim silent, the lam vowelled fatha, and ending in a dotted za, is Lahiq bin Humayd Sadusi, whose reliability was established earlier at 2543. The hadith was narrated by Muslim, as in al-Muntaqa, 1193 and 1194.