Schlürmann, J. (2019) “Jan Rüger: Heligoland. Britain, Germany, and the Struggle for the North Sea. Oxford University Press, 2017”., Historisk Tidsskrift, 118(2), s. 118:2, 559–562. Tilgængelig hos: https://tidsskrift.dk/historisktidsskrift/article/view/115526 (Set: 5 december 2025).