APA (7th ed.) Citation

Janssen, A., Alt, J., Pung, R., & Spring, P. (1998). Letters to the United States of America. Steyler Verlag.

Chicago Style (17th ed.) Citation

Janssen, Arnold, Josef Alt, Robert Pung, and Peter Spring. Letters to the United States of America. Nettetal: Steyler Verlag, 1998.

MLA (8th ed.) Citation

Janssen, Arnold, et al. Letters to the United States of America. Steyler Verlag, 1998.