The author cited as "de Beauchamp" should at all instances be corrected to "Beauchamp".
This was a French citizen (Paul Marais de Beauchamp), the "de" was a title of nobility (and also Marais) and is not cited if the surname stands alone like in a taxonomic name (same situation as in Lamarck, not de Lamarck, or Buffon, not de Buffon). There are about 20 instances at which names are attributed to this author and I did not open all names individually to post always the same message (the program would think this is spam).
The same applies to the author which was spelled "De Guerne", this should be corrected to "Guerne". These were only 3 instances, at which I have indicated the correction proposals individually. Must not be confounded with the convention that comes into effect at the name of "De Gaulle", here the "De" was not a title of nobility and is cited with the surname. In the name Baron Jules de Guerne the "de" was a title of nobility.