Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to say, "Duluk ash-shams begins from when the sun passes the meridian."  

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ كَانَ يَقُولُ دُلُوكُ الشَّمْسِ مَيْلُهَا  

Yahya related to me from Malik that Da'ud ibn al-Husayn said that someone had told him Abdullah ibn Abbas used to say, "Duluk ash-shams begins from when the sun passes the meridian. Ghasaq al-layl is the gathering of the night and its darkness."  

أَنَّ عَبْدَ اللَّهِ بْنَ عَبَّاسٍ كَانَ يَقُولُ دُلُوكُ الشَّمْسِ إِذَا فَاءَ الْفَىْءُ وَغَسَقُ اللَّيْلِ اجْتِمَاعُ اللَّيْلِ وَظُلْمَتُهُ