"Alqamah and I entered upon 'Abdullah bin Mas'ud and he said to us: 'Have these people prayed?' We said: 'No.' He said: 'Get up and pray.' So we went to stand behind him, and he put one of us on his right and the other on his left, and he prayed with no Adhan and no Iqamah. When he bowed he interlaced his fingers and placed his hands between his knees, and he said: 'I saw the Messenger of Allah ﷺ doing that.'"  

لَنَا أَصَلَّى هَؤُلاَءِ قُلْنَا لاَ قَالَ قُومُوا فَصَلُّوا فَذَهَبْنَا لِنَقُومَ خَلْفَهُ فَجَعَلَ أَحَدَنَا عَنْ يَمِينِهِ وَالآخَرَ عَنْ شِمَالِهِ فَصَلَّى بِغَيْرِ أَذَانٍ وَلاَ إِقَامَةٍ فَجَعَلَ إِذَا رَكَعَ شَبَّكَ بَيْنَ أَصَابِعِهِ وَجَعَلَهَا بَيْنَ رُكْبَتَيْهِ وَقَالَ هَكَذَا رَأَيْتُ رَسُولَ اللَّهِ ﷺ فَعَلَ  

"I heard Ibrahim (narrate) from 'Alqamah and Al-Aswad from 'Abdullah," and he narrated something similar.  

عَنْ عَبْدِ اللَّهِ فَذَكَرَ نَحْوَهُ