Schröder, H., Albrecht, R., & Guttenberg, G. (1981). 1870 - 1918. Beck.
Cita Chicago (17th ed.)Schröder, Hannelore, Regine Albrecht, i Gerda Guttenberg. 1870 - 1918. München: Beck, 1981.
Cita MLA (8th ed.)Schröder, Hannelore, et al. 1870 - 1918. Beck, 1981.
Atenció: Aquestes cites poden no estar 100% correctes.