Sunan Abi Dawud, Hadith 961 ⓘ
(There is another chain) from Yahya bin Sa'eed that Al-Qasim bin Muhammad saw them sitting in Tashah-hud, so he mentioned the Hadith.
حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، أَنَّ الْقَاسِمَ بْنَ مُحَمَّدٍ، أَرَاهُمُ الْجُلُوسَ فِي التَّشَهُّدِ فَذَكَرَ الْحَدِيثَ .
also referenced under: Hadith 957 (Hasan) & Book 3, Hadith 957 (USC-MSA)