There are 2 titles associated with this firm.

@book{ wphp_15969
  author={Opie,Amelia and Unknown,},
  year={1806},
  title={The Child's library of useful knowledge: containing a variety of entertaining and familiar stories, adapted to the capacities of children; interspersed with the history of birds. Calculated to form the mind and mould the heart to sympathy and love Vol. 1.},
  publisher={Zadok Cramer},
  address={Pittsburgh, PA},    }
@book{ wphp_15969
  author={Opie,Amelia and Unknown,},
  year={1806},
  title={The Child's library of useful knowledge: containing a variety of entertaining and familiar stories, adapted to the capacities of children; interspersed with the history of birds. Calculated to form the mind and mould the heart to sympathy and love Vol. 1.},
  publisher={Zadok Cramer},
  address={Pittsburgh, PA},    }