Karup Pedersen, O. (1991) “Ger van Roon: Small States in Years of Depression. The Oslo Alliance 1930-1940. Van Gorcurm, Assen/Maastricht, The Netherlands. 1989. 382 s”., Historisk Tidsskrift, 15(1), s. 329–330. doi: 10.7146/ht.v15i1.53365.