Title: Klausule opční (do Mírové konference pařížské r. 1919-1920)
Subjects: Citizenship, Self-determination, National, Paris Peace Conference (1919-1920), Paris Peace Conference (1919-1920) (uri) http://id.loc.gov/authorities/names/n80008740 (uri) http://viaf.org/viaf/sourceID/LC|n80008740