APA (7th ed.) Citation

Wagner, R., Spencer, S., & Millington, B. (1988). Selected letters of Richard Wagner (1st American ed.). W.W. Norton.

Chicago Style (17th ed.) Citation

Wagner, Richard, Stewart Spencer, and Barry Millington. Selected Letters of Richard Wagner. 1st American ed. New York: W.W. Norton, 1988.

MLA (9th ed.) Citation

Wagner, Richard, et al. Selected Letters of Richard Wagner. 1st American ed. W.W. Norton, 1988.