Muwatta Malik 311
موطأ مالك#311Sahihوَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ عُرْوَةَ بْنَ الزُّبَيْرِ، وَسَعِيدَ بْنَ الْمُسَيَّبِ، كَانَا يُصَلِّيَانِ النَّافِلَةَ وَهُمَا مُحْتَبِيَانِ .
Yahya related to me from Malik that he had heard that Urwa ibn az-Zubayr and Said ibn al-Musayyab used to pray voluntary prayers sitting
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Salim al-HilaliMaqtu Sahih
In-book reference: 8:25