University According to Humboldt History, Policy, and Future Possibilities Backhaus, Jürgen Georg Heftet / 2015 / Engelsk
200 Years of Friedrich Engels A Critical Assessment of His Life and Scholarship Backhaus, Jürgen Georg Innbundet / 2022 / Engelsk
200 Years of Friedrich Engels A Critical Assessment of His Life and Scholarship Backhaus, Jürgen Georg Heftet / 2023 / Engelsk