صَحِيحُ مُسْلِمٍ
Sahih Muslim 660 c
The Book of Mosques and Places of Prayer
It is permissible to offer voluntary prayers in congregation, and to pray on hasir (palm-fiber mats), khumrah (small mats), cloth, and other pure things
وَحَدَّثَنَاهُ مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، ح وَحَدَّثَنِيهِ زُهَيْرُ بْنُ حَرْبٍ، قَالَ حَدَّثَنَا عَبْدُ الرَّحْمَنِ، - يَعْنِي ابْنَ مَهْدِيٍّ - قَالَ حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ .
This hadith has also been narrated by Shu'ba with this chain of transmitters.
Sahih Muslim, 660 cSahihصحيح