Sheikh `Abd Al-Rahman Al-Sa`di (may Allah have mercy on him) said:

Allah, may He be exalted, said, telling His Messenger of that which was permissible for him (for marriage) as well as for the believers, “and the daughters of your paternal uncles and the daughters of your paternal aunts and the daughters of maternal uncles and the daughters of your maternal aunts”. This includes (daughters of) paternal uncles and aunts, maternal uncles and aunts, near and far.