There are 2 titles associated with this person.

@book{ wphp_350
  author={von Humboldt,Friedrich Heinrich Alexander},
  year={1814},
  title={Researches, Concerning the Institutions and Monuments of the Ancient Inhabitants of America, with Descriptions and Views of some of the most striking scenes in the Cordilleras! Written in French by Alexander de Humboldt and Translated into English by Helen Maria Williams.},
  publisher={Longman, Hurst, Rees, Orme, and Brown \& John Murray [32 Prince's Street] \& Henry Colburn [Conduit Street]},
  address={London},    }
@book{ wphp_1035
  author={Bonpland,Aimé Jacques Alexandre and von Humboldt,Friedrich Heinrich Alexander},
  year={1814-1821},
  title={Personal Narrative of Travels to the Equinoctial Regions of the New Continent During the Years 1799-1804. By Alexander de Humboldt, and Aimé Bonpland; with Maps, Plans, &c. Written in French by Alexander de Humboldt, and Translated into English by Helen Maria Williams.},
  publisher={Longman, Hurst, Rees, Orme, and Brown \& John Murray II [Albemarle] \& Henry Colburn [Conduit Street] \& Longman, Rees, Orme, Brown, and Green \& },
  address={London},    }