Sunan Abi Dawud 21504
In-book no 1000حَدَّثَنَا مُحَمَّدُ بْنُ سُلَيْمَانَ الأَنْبَارِيُّ، حَدَّثَنَا أَبُو نُعَيْمٍ، عَنْ مِسْعَرٍ، بِإِسْنَادِهِ وَمَعْنَاهُ قَالَ " أَمَا يَكْفِي أَحَدَكُمْ - أَوْ أَحَدَهُمْ - أَنْ يَضَعَ يَدَهُ عَلَى فَخِذِهِ ثُمَّ يُسَلِّمُ عَلَى أَخِيهِ مَنْ عَنْ يَمِينِهِ وَمَنْ عَنْ شِمَالِهِ " .
The aforesaid tradition has also been narrated by Mis’ar through a different chain of transmitters to the same effect. This version adds: Is it not sufficient for one of you or for one of them that he puts his hand on his thigh, and then gives the salutation to his brother to his right and left sides.