أَخْبَرَنَا عَلِيُّ بْنُ حُجْرٍ، قَالَ حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنَا حُمَيْدٌ، عَنْ أَنَسٍ، أَنَّ رَجُلاً، أَتَى النَّبِيَّ صلى الله عليه وسلم فَسَأَلَهُ عَنْ وَقْتِ صَلاَةِ الْغَدَاةِ فَلَمَّا أَصْبَحْنَا مِنَ الْغَدِ أَمَرَ حِينَ انْشَقَّ الْفَجْرُ أَنْ تُقَامَ الصَّلاَةُ فَصَلَّى بِنَا فَلَمَّا كَانَ مِنَ الْغَدِ أَسْفَرَ ثُمَّ أَمَرَ فَأُقِيمَتِ الصَّلاَةُ فَصَلَّى بِنَا ثُمَّ قَالَ ‏"‏ أَيْنَ السَّائِلُ عَنْ وَقْتِ الصَّلاَةِ مَا بَيْنَ هَذَيْنِ وَقْتٌ ‏"‏ ‏.‏

Humaid narrated from Ans that a man came to the Prophet (PBUH) and asked him about the time of the Subh prayer. The following morning he commanded that the Iqamah for prayer be said when dawn broke, and he led us in prayer. The next day when there was light he commanded that the Iqamah for prayer be said and he led us in prayer. Then he said: "Where is the one who was asking about the time for prayer? (It is) between these two times." Translation Not Available

Book Ref: Sunan An Nisai Book 6 Hadith 549
Web Ref:  Sunan An Nisai Vol 1 Book 6 Hadith 545