There are 3 titles associated with this firm.

@book{ wphp_1254
  author={Williams,Helen Maria},
  year={1816},
  title={On the Late Persecution of the Protestants in the South of France. By Helen Maria Williams.},
  publisher={Thomas and George Underwood \& },
  address={London},    }
@book{ wphp_12276
  author={Seward,Anna and Pratt,Samuel Jackson},
  year={1817},
  title={Monody on Major Andre; and Elegy on Captain Cook. Also Mr. Pratt's Sympathy. A Poem. Tenth Edition.},
  publisher={John Rodwell and Martin \& Longman, Hurst, Rees, Orme, and Brown \& Nathaniel Hailes [173 Piccadilly] \& John Taylor and James Augustus Hessey \& Thomas and George Underwood \& R. Jennings \& James Harper [London] \& John Otridge [1816-21] \& },
  address={London},    }
@book{ wphp_9141
  author={Stevens,Grace Buchanan},
  year={1818},
  title={Llewellen, or, The Vale of Phlinlimmon: A Novel. In Three Volumes},
  publisher={Macredie, Skelly, and Co. \& Thomas and George Underwood \& },
  address={Edinburgh},    }