وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ إِذَا جَمَعَ الأُمَرَاءُ بَيْنَ الْمَغْرِبِ وَالْعِشَاءِ فِي الْمَطَرِ جَمَعَ مَعَهُمْ ‏.‏

Yahya related to me from Malik from Nafi that Abdullah ibn Umarused to join the prayer along with the amirs if they joined maghriband isha in the rain. Translation Not Available

Book reference: Muwatta Imam Malik Book 9 Hadith 333
Web reference: Muwatta Imam Malik Book 9 Hadith 5