Sahih Muslim Book 4, Hadith Number 1933.

Chapter : Permissibility of women’s going out on ‘Id days towards the place of worship and their presence in the Khutba (sitting) at a distance from men.

Umm Atiyya reported: We were commanded to bring out on old days purdah-observing ladies and those unmarried, and menstruating women came out but remained behind people and pronounced takbir (Allah-o-Akbar) along with them.