Sahih Muslim 637
Sahih Muslim · Book 5: The Book of Mosques and Places of Prayer · The beginning of the time for Maghrib when the sun sets
وَحَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ الْحَنْظَلِيُّ ، أَخْبَرَنَا شُعَيْبُ بْنُ إِسْحَاقَ الدِّمَشْقِيُّ ، حَدَّثَنَا الأَوْزَاعِيُّ ، حَدَّثَنِي أَبُو النَّجَاشِيِّ ، حَدَّثَنِي رَافِعُ بْنُ خَدِيجٍ ، قَالَ كُنَّا نُصَلِّي الْمَغْرِبَ . بِنَحْوِهِ .
A hadith like this, i. e." We used to observe evening prayer...." so on and so forth, has been narrated by Rafi' b. Khadij by another chain of transmitters.