The Book of Mosques and Places of Prayer
5/19. Chapter:
As-Sahw (forgetfulness) in prayer and prostrating to compensate for it
Sahih Muslim
وَحَدَّثَنَاهُ يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا فُضَيْلُ بْنُ عِيَاضٍ، عَنْ مَنْصُورٍ، بِهَذَا الإِسْنَادِ وَقَالَ " فَلْيَتَحَرَّ الَّذِي يُرَى أَنَّهُ الصَّوَابُ " .
This hadith has been reported by Mansur with the same chain of transwitters and he said: " He should aim at what is according to him correct."
Reference : Sahih Muslim 572fIn-book reference : Book 5, Hadith 117USC-MSA web (English) reference : Book 4, Hadith 1173