There are 2 titles associated with this firm.

@book{ wphp_18414
  author={Marshall,Elizabeth},
  year={1819},
  title={A sketch of my friend's family, intended to suggest some practical hints on religion and domestic manners. By Mrs. Marshall, author of Henwick tales. Third edition.},
  publisher={Charles Ewer \& },
  address={Boston},    }
@book{ wphp_19364
  author={Rowson,Susanna},
  year={1824},
  title={Charlotte Temple. A tale of truth. By Mrs. Rowson, author of Victoria, The Inquisitor, Fille de chambre, &c. Two volumes in one. Last American edition.},
  publisher={Charles Ewer \& },
  address={Boston},    }