The Book of Mosques and Places of Prayer
حَدَّثَنَاهُ مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ مَنْصُورٍ، بِهَذَا الإِسْنَادِ وَقَالَ " فَلْيَتَحَرَّ أَقْرَبَ ذَلِكَ إِلَى الصَّوَابِ " .This hadith has been narrated by Mansur with the same chain of transmitters and said:" He should aim at correctness and that is right
From Sahih Muslim, whose reports the scholars accept as authentic.