Muwatta Malik 1106
موطأ مالك#1106SahihThese are the words of a Companion, not of the Prophet ﷺ. The chain is graded on its own terms.
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 ibn Malik said, "A virgin has seven nights, and a woman who has been previously married has three nights." Malik affirmed, "That is what is done among us." Malik added, "If the man has another wife, he divides his time equally between them after the wedding nights. He does not count the wedding nights against the one he has just married
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 28:16