There are 2 titles associated with this firm.

@book{ wphp_17941
  author={Hughes,Mary Robson},
  year={1815},
  title={An affectionate address to the poor. By the author of William's return, The twin brothers, and Henry Goodwin. Published by the Society for Promoting Christian Knowledge, Piety, and Charity.},
  publisher={The Society for Promoting Christian Knowledge, Piety, and Charity.},
  address={Boston},    }
@book{ wphp_17960
  author={Hughs,Mrs. Mary},
  year={1815},
  title={The sick man's friend; by the author of William's return;—The twin brothers, &c. Published by the Society for Promoting Christian Knowledge, Piety, and Charity.},
  publisher={The Society for Promoting Christian Knowledge, Piety, and Charity.},
  address={Boston},    }