أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ، قَالَ حَدَّثَنَا عَبْدُ اللَّهِ، عَنْ سُفْيَانَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْقَاسِمِ، عَنِ الْقَاسِمِ، عَنْ زَيْنَبَ بِنْتِ جَحْشٍ، قَالَتْ قُلْتُ لِلنَّبِيِّ صلى الله عليه وسلم إِنَّهَا مُسْتَحَاضَةٌ ‏.‏ فَقَالَ ‏"‏ تَجْلِسُ أَيَّامَ أَقْرَائِهَا ثُمَّ تَغْتَسِلُ وَتُؤَخِّرُ الظُّهْرَ وَتُعَجِّلُ الْعَصْرَ وَتَغْتَسِلُ وَتُصَلِّي وَتُؤَخِّرُ الْمَغْرِبَ وَتُعَجِّلُ الْعِشَاءَ وَتَغْتَسِلُ وَتُصَلِّيهِمَا جَمِيعًا وَتَغْتَسِلُ لِلْفَجْرِ ‏"‏ ‏.‏

It was narrated that Zainab bint Jahsh said: "I said to the Prophet (PBUH) that I was suffering from Istihadah. He said: 'Do not pray during the days of your period, then perform Ghusl and delay Zuhr and bring Maghrib and bring 'Isha' forward and pray them together, and perform Ghusl for Fajr." Translation Not Available

Book Ref: Sunan An Nisai Book 3 Hadith 361
Web Ref:  Sunan An Nisai Vol 1 Book 3 Hadith 361