كتاب الْمَسَاجِدِ وَمَوَاضِعِ الصَّلاَةِ
5  
The Book of Mosques and Places of Prayer
(19)
Chapter: As-Sahw (forgetfulness) in prayer and prostrating to compensate for it
(19)
باب السَّهْوِ فِي الصَّلاَةِ وَالسُّجُودِ لَهُ ‏
Sahih Muslim 572 g

This hadith has been narrated by Mansur and he said:

" He should aim at correctness."
وَحَدَّثَنَاهُ ابْنُ أَبِي عُمَرَ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ عَبْدِ الصَّمَدِ، عَنْ مَنْصُورٍ، بِإِسْنَادِ هَؤُلاَءِ وَقَالَ ‏ "‏ فَلْيَتَحَرَّ الصَّوَابَ ‏"‏ ‏.‏
Reference : Sahih Muslim 572g
In-book reference : Book 5, Hadith 118
USC-MSA web (English) reference : Book 4, Hadith 1174
  (deprecated numbering scheme)