APA (7th ed.) Citation

Yeats, W. B., Alspach, C. C., & Alspach, R. K. (1966). The variorum edition of the plays of W.B. Yeats. Macmillan.

Chicago Style (17th ed.) Citation

Yeats, W. B., Catharine C. Alspach, and Russell K. Alspach. The Variorum Edition of the Plays of W.B. Yeats. London: Macmillan, 1966.

MLA (8th ed.) Citation

Yeats, W. B., et al. The Variorum Edition of the Plays of W.B. Yeats. Macmillan, 1966.