Sunan Ibn Majah, Volume 2, Book 5, Hadith 1153 (DarusSalam) ⓘ
It was narrated that ‘Abdullah bin Malik bin Buhainah said: “The Prophet passed by a man who was praying when the Iqamah for Subh prayer had been called, and he said something to him, I do not know what he said. When he finished, we surrounded the man and asked him: ‘What did the Messenger of Allah say to you?’ He said: ‘He said to me: “Soon one of you will pray Fajr with four Rak’ah.’”
حَدَّثَنَا أَبُو مَرْوَانَ، مُحَمَّدُ بْنُ عُثْمَانَ الْعُثْمَانِيُّ حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، عَنْ أَبِيهِ، عَنْ حَفْصِ بْنِ عَاصِمٍ، عَنْ عَبْدِ اللَّهِ بْنِ مَالِكِ ابْنِ بُحَيْنَةَ، قَالَ مَرَّ النَّبِيُّ ـ صلى الله عليه وسلم ـ بِرَجُلٍ وَقَدْ أُقِيمَتْ صَلاَةُ الصُّبْحِ وَهُوَ يُصَلِّي فَكَلَّمَهُ بِشَىْءٍ لاَ أَدْرِي مَا هُوَ فَلَمَّا انْصَرَفَ أَحَطْنَا بِهِ نَقُولُ لَهُ مَاذَا قَالَ لَكَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ قَالَ قَالَ لِي " يُوشِكُ أَحَدُكُمْ أَنْ يُصَلِّيَ الْفَجْرَ أَرْبعًا " .
also referenced under: Hadith 1153 (Reference) & Book 5, Hadith 1208 (In-Book)