Helmbold, T., & Romain, L. (1988). Thomas Helmbold. Ritter.
Cita Chicago (17th ed.)Helmbold, Thomas, i Lothar Romain. Thomas Helmbold. München: Ritter, 1988.
Cita MLA (8th ed.)Helmbold, Thomas, i Lothar Romain. Thomas Helmbold. Ritter, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.