There are 2 titles associated with this firm.

@book{ wphp_15099
  author={Oswald,Margaret},
  year={1811},
  title={A Sketch of the Most Remarkable Scenery, near Callander of Monteath; Particularly, the Trossachs, at the East End of Loch Catherine, and the Road by Lochearn-Head to Duneira. The Fifth Edition Improved.},
  publisher={Dougal M'Gregor},
  address={Stirling},    }
@book{ wphp_15101
  author={Oswald,Margaret},
  year={1820},
  title={A Sketch of the Most Remarkable Scenery near Callander of Monteath; Particularly, the Trossachs at the East End of Loch Catherine, and the Road by Lochearn-Head to Duneira. Seventh Edition.},
  publisher={Dougal M'Gregor},
  address={Glasgow},    }