وَإِن كُنتُمۡ فِي رَيۡبٖ مِّمَّا نَزَّلۡنَا عَلَىٰ عَبۡدِنَا فَأۡتُواْ بِسُورَةٖ مِّن مِّثۡلِهِۦ وَٱدۡعُواْ شُهَدَآءَكُم مِّن دُونِ ٱللَّهِ إِن كُنتُمۡ صَٰدِقِينَ
Wa in kuntum fee raibim mimmaa nazzalnaa 'alaa 'abdinaa fatoo bi Sooratim mim mislihee wad'oo shuhadaaa'akum min doonil laahi in kuntum saadiqeen
English Translation
And if you are in doubt about what We have sent down upon Our Servant [Muhammad], then produce a surah the like thereof and call upon your witnesses other than Allah, if you should be truthful
— Saheeh International