Muwatta Imam Malik Book of Marriage, Hadith 12
Yahya related to me from Malik from Yahya ibn Said from Said ibn al-Musayyab that 'Umar ibn al-Khattab decided about the woman who was married by a man and the marriage had been consummated, that the bride-price was obligatory.
حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، قَضَى فِي الْمَرْأَةِ إِذَا تَزَوَّجَهَا الرَّجُلُ أَنَّهُ إِذَا أُرْخِيَتِ السُّتُورُ فَقَدْ وَجَبَ الصَّدَاقُ .