Muwatta Malik 1102

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 ‏.‏

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

Reference

Muwatta Malik 1102

In-book

Book 28, Hadith 12