Ayçoberry Pierre. Jonathan Sperber, Rhineland Radicals. The Democratic Movement and the Revolution of 1848-1849. In: Annales. Économies, Sociétés, Civilisations. 47ᵉ année, N. 4-5, 1992. pp. 1041-1043.
Ayçoberry Pierre. Jonathan Sperber, Rhineland Radicals. The Democratic Movement and the Revolution of 1848-1849. In: Annales. Économies, Sociétés, Civilisations. 47ᵉ année, N. 4-5, 1992. pp. 1041-1043.