كتاب الحيض
3  
The Book of Menstruation
(15)
Chapter: A menstruating woman is obliged to make up missed fasts but not prayers
(15)
باب وُجُوبِ قَضَاءِ الصَّوْمِ عَلَى الْحَائِضِ دُونَ الصَّلاَةِ ‏
Sahih Muslim 335 c

Mu'adha said:

I asked 'A'isha: What is the reason that a menstruating woman completes the fasts (that she abandons during her monthly course). but she does not complete the prayers? She (Hadrat 'A'isha) said: Are you a Haruriya? I said: I am not a Haruriya, but I simply want to inquire. She said: We passed through this (period of menstruation), and we were ordered to complete the fasts, but were not ordered to complete the prayers.
وَحَدَّثَنَا عَبْدُ بْنُ حُمَيْدٍ، أَخْبَرَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنْ عَاصِمٍ، عَنْ مُعَاذَةَ، قَالَتْ سَأَلْتُ عَائِشَةَ فَقُلْتُ مَا بَالُ الْحَائِضِ تَقْضِي الصَّوْمَ وَلاَ تَقْضِي الصَّلاَةَ فَقَالَتْ أَحَرُورِيَّةٌ أَنْتِ قُلْتُ لَسْتُ بِحَرُورِيَّةٍ وَلَكِنِّي أَسْأَلُ ‏.‏ قَالَتْ كَانَ يُصِيبُنَا ذَلِكَ فَنُؤْمَرُ بِقَضَاءِ الصَّوْمِ وَلاَ نُؤْمَرُ بِقَضَاءِ الصَّلاَةِ ‏.‏
Reference : Sahih Muslim 335c
In-book reference : Book 3, Hadith 85
USC-MSA web (English) reference : Book 3, Hadith 662
  (deprecated numbering scheme)