Hadith 24:429
Sahih (Darussalam)
It was narrated that Abdur-Rahman bin Yazid said:
"When we were in Jam (Al-Muzadalifah), Ibn Masud said: 'I heard the one to whoem surat Al-Baqarah was revealed say, in this place: Labbaik Allahumma Labbaik."
أَخْبَرَنَا هَنَّادُ بْنُ السَّرِيِّ، فِي حَدِيثِهِ عَنْ أَبِي الأَحْوَصِ، عَنْ حُصَيْنٍ، عَنْ كَثِيرٍ، - وَهُوَ ابْنُ مُدْرِكٍ - عَنْ عَبْدِ الرَّحْمَنِ بْنِ يَزِيدَ، قَالَ قَالَ ابْنُ مَسْعُودٍ وَنَحْنُ بِجَمْعٍ سَمِعْتُ الَّذِي، أُنْزِلَتْ عَلَيْهِ سُورَةُ الْبَقَرَةِ يَقُولُ فِي هَذَا الْمَكَانِ " لَبَّيْكَ اللَّهُمَّ لَبَّيْكَ "
Original Reference: Sunan an-Nasa'i 3046