كتاب الحج
15  
The Book of Pilgrimage
(49)
Chapter: It is recommended to send the weak among women and others ahead from Al-Muzdalifah to Mina at the end of the night, before it gets crowded, but it is recommended for others to stay there until they have prayed Subh in Al-Muzdalifah
(49)
باب اسْتِحْبَابِ تَقْدِيمِ دَفْعِ الضَّعَفَةِ مِنَ النِّسَاءِ وَغَيْرِهِنَّ مِنْ مُزْدَلِفَةَ إِلَى مِنًى فِي أَوَاخِرِ اللَّيَالِي قَبْلَ زَحْمَةِ النَّاسِ وَاسْتِحْبَابِ الْمُكْثِ لِغَيْرِهِمْ حَتَّى يُصَلُّوا الصُّبْحَ بِمُزْدَلِفَةَ
Sahih Muslim 1292 a

Ibn Shawwal (the freed slave of Umm Habiba) reported that he went to Umm Habiba (the wife of Allah's Apostle) who informed him that Allah's Apostle (ﷺ) sent her from Muzdalifa during the night.

حَدَّثَنِي مُحَمَّدُ بْنُ حَاتِمٍ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، ح وَحَدَّثَنِي عَلِيُّ بْنُ خَشْرَمٍ، أَخْبَرَنَا عِيسَى، جَمِيعًا عَنِ ابْنِ جُرَيْجٍ، أَخْبَرَنِي عَطَاءٌ، أَنَّ ابْنَ شَوَّالٍ، أَخْبَرَهُ أَنَّهُ، دَخَلَ عَلَى أُمِّ حَبِيبَةَ فَأَخْبَرَتْهُ أَنَّ النَّبِيَّ صلى الله عليه وسلم بَعَثَ بِهَا مِنْ جَمْعٍ بِلَيْلٍ ‏.‏
Reference : Sahih Muslim 1292a
In-book reference : Book 15, Hadith 328
USC-MSA web (English) reference : Book 7, Hadith 2963
  (deprecated numbering scheme)