Peter Forsskal: Thoughts on Civil Liberty
  Forsskål´s descriptions of the animal and plant species collected during the Arabian expedition were published and posthumously edited by Carsten Niebuhr as well as illustrations concerning them drawn by  G.W. Baurenfeind. They are available online via Biological Heritage Library; although other online resources are also available.
  Descriptiones Animalium: Avium, Amphibiorum, Piscium, Insectorum, Vermium, quae in itinere orientali observavit Petrus Forskål, post mortem edidit Carsten Niebuhr. Hauniae, 1775.
  Flora Aegyptiaco-Arabica sive descriptiones plantarum quas per Aegyptum inferiorem at Arabiam felicem detexit, illustravit Petrus Forskål,, post mortem edidit Carsten Niebuhr. Hauniae, 1775
  Icones rerum naturalium, quas in itinere orientali depingi curavit Petrus Forskål, post mortem auctoris edidit Carsten Niebuhr. Hauniae, 1776