وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ حُمَيْدٍ الطَّوِيلِ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّهُ كَانَ يَقُولُ لِلْبِكْرِ سَبْعٌ وَلِلثَّيِّبِ ثَلاَثٌ ‏.‏

Yahya related to me from Malik from Humayd at-Tawil that Anas ibnMalik said, "A virgin has seven nights, and a woman who has beenpreviously married has three nights." Malik affirmed, "Thatis what is done among us." Malik added, "If the man hasanother wife, he divides his time equally between them after thewedding nights. He does not count the wedding nights against the onehe has just married." Translation Not Available

Book Ref: Muwatta Imam Malik Book 28 Hadith 1109
Web Ref:  Muwatta Imam Malik Book 28 Hadith 15