"The month is like this," and (one of the narrators) Shubah did the same gesture as Jabalah had done, copying, Ibn 'Umar: "It is twenty-nine, as he gestured twice with all fingers of both hands, and putting down one of his fingers the third time." (Using translation from Nasāʾī 2142)
عَنِ النَّبِيِّ ﷺ قَالَ «الشَّهْرُ هَكَذَا» وَوَصَفَ شُعْبَةُ عَنْ صِفَةِ جَبَلَةَ عَنْ صِفَةِ ابْنِ عُمَرَ أَنَّهُ تِسْعٌ وَعِشْرُونَ فِيمَا حَكَى مِنْ صَنِيعِهِ مَرَّتَيْنِ بِأَصَابِعِ يَدَيْهِ وَنَقَصَ فِي الثَّالِثَةِ إصْبُعًا مِنْ أَصَابِعِ يَدَيْهِ