There are 2 titles associated with this person.

@book{ wphp_15665
  author={Astell,Mary},
  year={1696},
  title={An Essay in Defence of the Female Sex. In which are inserted characters of a pedant, a squire, a beau, a vertuoso, a poetaster, a city-critick, &c. In a letter to a lady. Written by a lady.},
  publisher={Abel Roper II and Elizabeth Wilkinson \& Robert Clavel},
  address={London},    }
@book{ wphp_15668
  author={Astell,Mary},
  year={1696},
  title={An Essay in Defence of the Female Sex. In which are inserted characters of a pedant, a squire, a beau, a vertuoso, a poetaster, a city-critick, &c. In a letter to a lady. Written by a lady. The second edition.},
  publisher={Abel Roper II and Elizabeth Wilkinson \& Robert Clavel},
  address={London},    }