وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ ابْنَ عُمَرَ، أَقَامَ بِمَكَّةَ عَشْرَ لَيَالٍ يَقْصُرُ الصَّلاَةَ إِلاَّ أَنْ يُصَلِّيَهَا مَعَ الإِمَامِ فَيُصَلِّيهَا بِصَلاَتِهِ ‏.‏

Yahya related to me from Malik from Nafi that Ibn Umar stayed inMakka for ten nights, shortening the prayer, except when he prayed itbehind an imam, in which case he followed the imam's prayer. Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 347
Web Ref:  Muwatta Imam Malik Book 9 Hadith 19

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