I was shown Lailat-ul-Qadr; then I was made to forget it, and saw that I was prostrating in water and clay in the morning of that (night). He (the narrator) said: There was a downpour on the twenty-third night and the Messenger of Allah ﷺ led us in prayer, and as he went back, there was a trace of water and clay on his forehead and on his nose. He (the narrator) said: 'Abdullah b. Unais used to say that it was the twenty-third (night). (Using translation from Muslim 1168)
أَنَّ رَسُولَ اللهِ ﷺ قَالَ أُرِيتُ لَيْلَةَ الْقَدْرِ ثُمَّ أُنْسِيتُهَا وَأَرَانِي صَبِيحَتَهَا أَسْجُدُ فِي مَاءٍ وَطِينٍ قَالَ فَمُطِرْنَا لَيْلَةَ ثَلَاثٍ وَعِشْرِينَ فَصَلَّى بِنَا رَسُولُ اللهِ ﷺ ثُمَّ انْصَرَفَ وَإِنَّ أَثَرَ الْمَاءِ وَالطِّينِ لَعَلَى أَنْفِهِ وَجَبْهَتِهِ قَالَ وَكَانَ عَبْدُ اللهِ بْنُ أُنَيْسٍ يَقُولُ ثَلَاثٌ وَعِشْرُونَ لَفْظُ حَدِيثِ أَبِي عَبْدِ اللهِ