Sahih Muslim 1152:

Sahl b. Sa’d (Allah be pleased with him) reported Allah’s Messenger (ﷺ) as saying: In Paradise there is a gate which is called Rayyan through which only the people who fast would enter on the Day on Resurrection. None else would enter along with them. It would be proclaimed: Where are the people who fast that they should be admitted into it? And when the last of them would enter, it would be closed and no one would enter it.[ Sahih Muslim 1152 ]

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا خَالِدُ بْنُ مَخْلَدٍ، – وَهُوَ الْقَطَوَانِيُّ – عَنْ سُلَيْمَانَ، بْنِ بِلاَلٍ حَدَّثَنِي أَبُو حَازِمٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، – رضى الله عنه – قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ “‏ إِنَّ فِي الْجَنَّةِ بَابًا يُقَالُ لَهُ الرَّيَّانُ يَدْخُلُ مِنْهُ الصَّائِمُونَ يَوْمَ الْقِيَامَةِ لاَ يَدْخُلُ مَعَهُمْ أَحَدٌ غَيْرُهُمْ يُقَالُ أَيْنَ الصَّائِمُونَ فَيَدْخُلُونَ مِنْهُ فَإِذَا دَخَلَ آخِرُهُمْ أُغْلِقَ فَلَمْ يَدْخُلْ مِنْهُ أَحَدٌ ‏”‏ ‏.‏

Reference : Sahih Muslim 1152
In-book reference : Book 13, Hadith 216
Web Ref: https://sunnah.com/muslim/13/216
Sahih Bukhari Ref: http://islam.thestraightwayoflife.com/raiyan-or-rayyan-sahih-al-bukhari-1896