Does any one know about suleyman the magnificants mother, her name was Hafssa or Hafiza Khatoun?

Hafssa sultan, sometimes called Hafiza Khatoun was the mother of suleyman the magnificant. he was the sultan of the ottoman empire and his father is selim the I. i basically just want know more about her for my report but i cant find much information. if anyone knows of any books or websites i'd really appreciate it. thanks.