كتاب الرضاع
17  
The Book of Suckling
(9)
Chapter: It is permissible to have intercourse with a female captive after it is established that she is not pregnant, and if she has a husband, then her marriage is annulled when she is captured
(9)
باب جَوَازِ وَطْءِ الْمَسْبِيَّةِ بَعْدَ الاِسْتِبْرَاءِ وَإِنْ كَانَ لَهَا زَوْجٌ انْفَسَخَ نِكَاحُهَا بِالسَّبْي
Sahih Muslim 1456 d

This hadith has been reported on the authority of AbuSa'id (al-Khudri) (Allah be pleased with him) through another chain of transmitters and the words are:

They took captives (women) on the day of Autas who had their husbands. They were afraid (to have sexual intercourse with them) when this verse was revealed:" And women already married except those whom you right hands posses" (iv. 24)
وَحَدَّثَنِيهِ يَحْيَى بْنُ حَبِيبٍ الْحَارِثِيُّ، حَدَّثَنَا خَالِدُ بْنُ الْحَارِثِ، حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، عَنْ أَبِي الْخَلِيلِ، عَنْ أَبِي سَعِيدٍ، قَالَ أَصَابُوا سَبْيًا يَوْمَ أَوْطَاسٍ لَهُنَّ أَزْوَاجٌ فَتَخَوَّفُوا فَأُنْزِلَتْ هَذِهِ الآيَةُ ‏{‏ وَالْمُحْصَنَاتُ مِنَ النِّسَاءِ إِلاَّ مَا مَلَكَتْ أَيْمَانُكُمْ‏}‏ ‏.‏
Reference : Sahih Muslim 1456d
In-book reference : Book 17, Hadith 43
USC-MSA web (English) reference : Book 8, Hadith 3433
  (deprecated numbering scheme)