Sunan Abi Dawud 1213
سنن أبي داود#1213Sahihحَدَّثَنَا إِبْرَاهِيمُ بْنُ مُوسَى الرَّازِيُّ، أَخْبَرَنَا عِيسَى، عَنِ ابْنِ جَابِرٍ، بِهَذَا الْمَعْنَى . قَالَ أَبُو دَاوُدَ وَرَوَاهُ عَبْدُ اللَّهِ بْنُ الْعَلاَءِ عَنْ نَافِعٍ، قَالَ حَتَّى إِذَا كَانَ عِنْدَ ذَهَابِ الشَّفَقِ نَزَلَ فَجَمَعَ بَيْنَهُمَا .
This tradition has also been transmitted by Ibrahim b. Musa al-Razi, from 'Isa, on the authority of Ibn Jabir to the same effect. Abu Dawud said:'Abd Allah b. al-'Ala' narrated on the authority of Nafi' saying: When the twilight was about to disappear, he alighted and combined both (the prayers)
Scholarly Authentication
The label above is the grade most of these scholars gave, each scholar counted once — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. When they judged only its chain of narrators (“Isnaad”), the label says “Sound chain”. Each scholar's own wording:
Our source also lists this ruling under Muhammad Muhyi Al-Din Abdul Hamid, the editor of the printed edition it was taken from. It is al-Albani's ruling printed again, so it is counted once.
In-book reference: 4:16