وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ لاَ يَتَحَرَّ أَحَدُكُمْ فَيُصَلِّيَ عِنْدَ طُلُوعِ الشَّمْسِ وَلاَ عِنْدَ غُرُوبِهَا ‏"‏ ‏.‏

Yahya related to me from Malik from Nafi from Abdullah ibn Umarthat the Messenger of Allah, may Allah bless him and grant him peace,said, "You should not intend to pray either at sunrise or sunset." Translation Not Available

Book Ref: Muwatta Imam Malik Book 15 Hadith 519
Web Ref:  Muwatta Imam Malik Book 15 Hadith 47