Yahya related to me from Malik that Da'ud ibn al-Husayn said thatsomeone had told him Abdullah ibn Abbas used to say, "Duluk ash-shamsbegins from when the sun passes the meridian. Ghasaq al-layl is thegathering of the night and its darkness." (IT)
Arabic/English book reference (IT): Book 1, Hadith 20 (IT)