Surah Hud, Verse 13
أَمْ يَقُولُونَ ٱفْتَرَىٰهُ ۖ قُلْ فَأْتُوا۟ بِعَشْرِ سُوَرٍۢ مِّثْلِهِۦ مُفْتَرَيَٰتٍۢ وَٱدْعُوا۟ مَنِ ٱسْتَطَعْتُم مِّن دُونِ ٱللَّهِ إِن كُنتُمْ صَٰدِقِينَ
Translation — Sahih International
Or do they say, "He invented it"? Say, "Then bring ten surahs like it that have been invented and call upon [for assistance] whomever you can besides Allah, if you should be truthful."
Source
Kur'an-ı Kerim, Hûd Suresi 11:13
https://kuran.diyanet.gov.tr/mushaf/kuran-meal-2/11-suresi-13-ayet