Sunan Ibn Majah Book 5, Hadith 1163

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، قَالَ سَمِعْتُ عَلِيَّ بْنَ زَيْدِ بْنِ جُدْعَانَ، قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ، يَقُولُ إِنْ كَانَ الْمُؤَذِّنُ لَيُؤَذِّنُ عَلَى عَهْدِ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فَيُرَى أَنَّهَا الإِقَامَةُ مِنْ كَثْرَةِ مَنْ يَقُومُ فَيُصَلِّي الرَّكْعَتَيْنِ قَبْلَ الْمَغْرِبِ ‏.‏

‘Ali bin Zaid bin Jud’an said:“I heard Anas bin Malik say: ‘The Mu ’adh-dhin would call the Adhan during the time of the Messenger of Allah (ﷺ), and one would think that it was the Iqamah because there were so many people who stood and performed the two Rak’ah before the Maghrib.”