There are 3 titles associated with this person.

@book{ wphp_14699
  author={Liddon,John},
  year={1792},
  title={Cruelty the natural and inseparable consequence of slavery, and both diametrically opposite to the doctrine and spirit of the Christian religion: represented in a sermon, preached on Sunday, March 11th, 1792, at Hemel-Hempstead, Herts. By John Liddon.},
  publisher={},
  address={London},    }
@book{ wphp_14712
  author={Liddon,John},
  year={1792},
  title={The general religious instruction of the poor, the surest means of promoting universal national happiness: represented in a sermon, preached on Sunday, September 30, 1792, at Hemel-Hempstead, Herts; for the benefit of the Sunday-schools established in that town, ... By John Liddon.},
  publisher={},
  address={London},    }
@book{ wphp_14713
  author={Liddon,John},
  year={1793},
  title={The genuine principles of all religious dissent, and especially of the Protestant dissenters in England, illustrated and defended: a sermon, delivered on Sunday, November 4, 1792, to the congregation of Protestant dissenters, in Hemel-Hempstead. By John Liddon.},
  publisher={},
  address={London},    }