Musnad Ahmad 950, 951, 952
It was narrated that Sa`eed bin Wahb. and Zaid bin Yuthai’ said:
‘Ali adjured the people at ar-Rahbah, saying: Whoever heard the messenger of Allah (ﷺ) speak on the day of Ghadeer Khumm, let him stand up. And (of the people) around Sa’eed, six men stood up, and (of the people) around Zaid, six men stood up, and they testified that they had heard the Messenger of Allah (ﷺ) say to ‘Ali (رضي الله عنه) on the day of Ghadeer Khumm. “Isn`t it Allah Who is closer to the believers?” They said: Yes. He said: `O Allah, if I am a person`s mawla (friend and supporter) then ‘Ali is also his mawla; O Allah, take as friends those who take him as a friend, and take as enemies those who take him as an enemy.”

A hadeeth like that of Abu Ishaq was narrated from `Amr Dhi Murr, i.e., from Sa`eed and Zaid, and he added to it: `and support those who support him, and forsake those who forsake him.`

A similar report was narrated from Abut-Tufail from Zaid bin Arqam from the Prophet (ﷺ).
حَدَّثَنَا عَبْد اللَّهِ، حَدَّثَنَا عَلِيُّ بْنُ حَكِيمٍ الْأَوْدِيُّ، أَنْبَأَنَا شَرِيكٌ، عَنْ أَبِي إِسْحَاقَ، عَنْ سَعِيدِ بْنِ وَهْبٍ، وَعَنْ زَيْدِ بْنِ يُثَيْعٍ، قَالَا نَشَدَ عَلِيٌّ النَّاسَ فِي الرَّحَبَةِ مَنْ سَمِعَ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ يَوْمَ غَدِيرِ خُمٍّ إِلَّا قَامَ قَالَ فَقَامَ مِنْ قِبَلِ سَعِيدٍ سِتَّةٌ وَمِنْ قِبَلِ زَيْدٍ سِتَّةٌ فَشَهِدُوا أَنَّهُمْ سَمِعُوا رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ لِعَلِيٍّ رَضِيَ اللَّهُ عَنْهُ يَوْمَ غَدِيرِ خُمٍّ أَلَيْسَ اللَّهُ أَوْلَى بِالْمُؤْمِنِينَ قَالُوا بَلَى قَالَ اللَّهُمَّ مَنْ كُنْتُ مَوْلَاهُ فَعَلِيٌّ مَوْلَاهُ اللَّهُمَّ وَالِ مَنْ وَالَاهُ وَعَادِ مَنْ عَادَاهُ.
حَدَّثَنَا عَبْد اللَّهِ حَدَّثَنَا عَلِيُّ بْنُ حَكِيمٍ أَنْبَأَنَا شَرِيكٌ عَنْ أَبِي إِسْحَاقَ عَنْ عَمْرٍو ذِي مُرٍّ بِمِثْلِ حَدِيثِ أَبِي إِسْحَاقَ يَعْنِي عَنْ سَعِيدٍ وَزَيْدٍ وَزَادَ فِيهِ وَانْصُرْ مَنْ نَصَرَهُ وَاخْذُلْ مَنْ خَذَلَهُ.
حَدَّثَنَا عَبْد اللَّهِ حَدَّثَنَا عَلِيٌّ أَنْبَأَنَا شَرِيكٌ عَنِ الْأَعْمَشِ عَنْ حَبِيبِ بْنِ أَبِي ثَابِتٍ عَنْ أَبِي الطُّفَيْلِ عَنْ زَيْدِ بْنِ أَرْقَمَ عَنْ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِثْلَهُ‏.‏