The Book of the Times (of Prayer)
6/30. Chapter:
Whoever Catches Up With A Rak'ah Of The Prayer
Sunan an-Nasai
أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ أَبِي سَلَمَةَ، عَنْ أَبِي هُرَيْرَةَ، . أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " مَنْ أَدْرَكَ مِنَ الصَّلاَةِ رَكْعَةً فَقَدْ أَدْرَكَ الصَّلاَةَ " .
It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said: "Whoever catches up with a Rak'ah of the prayer, then he has caught up with the prayer."
Reference : Sunan an-Nasa'i 553In-book reference : Book 6, Hadith 60English translation : Vol. 1, Book 6, Hadith 554