(i) 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.
Sahih Muslim Book 003, Number 0662:
(ii) Narrated 'Aisha:The Prophet said to me, "Give up the prayer when your menses begin and when it has finished, wash the blood off your body (take a bath) and start praying."
Volume 1, Book 6, Number 327: