APA (7th ed.) Citation

Nielsen, B., Schier, H., & Suffredini, A. (1995). Ultimate German advanced. Living Language.

Chicago Style (17th ed.) Citation

Nielsen, Birgit, Helga Schier, and Ana Suffredini. Ultimate German Advanced. New York: Living Language, 1995.

MLA (9th ed.) Citation

Nielsen, Birgit, et al. Ultimate German Advanced. Living Language, 1995.