On geographical publications in Germany in the 19th century acknowledgment of the state of Vietnam's owning of the Paracel Islands in 1816

In order to contribute to enriching historical documents with international legal value to prove Vietnam's legal sovereignty over geographical features in the Hoang Sa and Truong Sa archipelagoes, in this article we select select and provide readers with content and accompanying illustrations of publications in Germany in the nineteenth century referring to the state's official possession of the Paracels and Spratlys in 1816 of the king of Vietnam and has been recognized by the international community. Publications on this subject are divided into three types: translations from works outside Germany; Geography edition of German scholars and German encyclopedia edition.