Al Baqarah Ayah 23

وَإِن كُنتُمْ فِى رَيْبٍ مِّمَّا نَزَّلْنَا عَلَىٰ عَبْدِنَا فَأْتُواْ بِسُورَةٍ مِّن مِّثْلِهِۦ وَٱدْعُواْ شُهَدَآءَكُم مِّن دُونِ ٱللَّهِ إِن كُنتُمْ صَـٰدِقِينَ ٢٣ And if you are in doubt about what We have revealed to Our servant, then produce a sûrah like it and call your helpers other than Allah, if what you say is true.