On his return to Bonn he studied Arabic, and took the degree of Ph.D., his dissertation discussing the Arabic notices of the geography of the Punjab ("Commentario geographica historica de Pentapotamia Indica", Bonn, 1827).
Его диссертация касалась арабских сообщений о географии Пенджаба ("Commentario geographica historica de Pentapotamia Indica", Бонн, 1827).