Prayer (Kitab Al-Salat)
2/187. Chapter:
How Should One Sit In The Tashah-hud
Sunan Abi Dawud
حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، أَنَّ الْقَاسِمَ بْنَ مُحَمَّدٍ، أَرَاهُمُ الْجُلُوسَ فِي التَّشَهُّدِ فَذَكَرَ الْحَدِيثَ .
(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.
Reference : Sunan Abi Dawud 961In-book reference : Book 2, Hadith 572English translation : Book 2, Hadith 957