1
عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو رضي الله عنهما قَالَ: (رَأَيْتُ النَّبيَّ صلى الله عليه وسلم يَعْقِدُ التَّسْبِيحَ) وفي زيادةٍ: (بِيَمِينِهِ)
It was narrated that 'Abdullah bin 'Amr (may Allah be pleased with them both) said: 'I saw the Prophet (peace be upon him) counting the glorifications (tasbih) on his fingers' — and in another narration: 'with his right hand.'
Source: Abu Dawud, At-Tirmizi 5/521.