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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bayhaqi:4770 – Abū Mijlaz > Saʾalt Ibn ʿUmar > al-Witr

[Machine] I heard the Messenger of Allah, ﷺ , say, "A unit of night prayer."  

البيهقي:٤٧٧٠ – وَبِإِسْنَادِهِ عَنْ أَبِي مِجْلَزٍ قَالَ سَأَلْتُ ابْنَ عُمَرَ عَنِ الْوِتْرِ فَقَالَ

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ رَكْعَةٌ مِنْ آخِرِ اللَّيْلِ  

أَخْرَجَهُ مُسْلِمٌ فِي الصَّحِيحِ مِنْ حَدِيثِ هَمَّامِ بْنِ يَحْيَى

See similar narrations below:

Collected by Ṭabarānī, Bayhaqī
tabarani:12905 – Muʿādh b. al-Muthanná > Musaddad > Yaḥyá b. Saʿīd > Shuʿbah > Qatādah > Abū Mijlaz > Saʾalt Ibn ʿAbbās > al-Witr

I asked Ibn 'Abbas about the Witr prayer. He said: I heard the Messenger of Allah ﷺ as saying: It is a rak'ah at the end of the night prayer. (Using translation from Muslim 753)  

الطبراني:١٢٩٠٥ – حَدَّثَنَا مُعَاذُ بْنُ الْمُثَنَّى ثنا مُسَدَّدٌ ثنا يَحْيَى بْنُ سَعِيدٍ عَنْ شُعْبَةَ حَدَّثَنِي قَتَادَةُ عَنْ أَبِي مِجْلَزٍ قَالَ سَأَلْتُ ابْنَ عَبَّاسٍ عَنِ الْوِتْرِ فَقَالَ

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ «رَكْعَةٌ مِنْ آخِرِ اللَّيْلِ»  

bayhaqi:4769 – Abū Bakr Muḥammad b. al-Ḥasan b. Fūrak > ʿAbdullāh b. Jaʿfar > Yūnus b. Ḥabīb > Abū Dāwud > Hammām > Qatādah > Abū Mijlaz > Saʾalt Ibn ʿAbbās > al-Witr

[Machine] I heard the Messenger of Allah ﷺ saying, "A prayer during the late hours of the night."  

البيهقي:٤٧٦٩ – وَأَخْبَرَنَا أَبُو بَكْرٍ مُحَمَّدُ بْنُ الْحَسَنِ بْنِ فُورَكٍ أنبأ عَبْدُ اللهِ بْنُ جَعْفَرٍ ثنا يُونُسُ بْنُ حَبِيبٍ ثنا أَبُو دَاوُدَ ثنا هَمَّامٌ عَنْ قَتَادَةَ عَنْ أَبِي مِجْلَزٍ قَالَ سَأَلْتُ ابْنَ عَبَّاسٍ عَنِ الْوِتْرِ فَقَالَ

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ رَكْعَةٌ مِنْ آخِرِ اللَّيْلِ