APA (7th ed.) Citation

Goold, R., Power, B., & Pirandello, L. (2008). Six characters in search of an author. Nick Hern Books.

Chicago Style (17th ed.) Citation

Goold, Rupert, Ben Power, and Luigi Pirandello. Six Characters in Search of an Author. London: Nick Hern Books, 2008.

MLA (9th ed.) Citation

Goold, Rupert, et al. Six Characters in Search of an Author. Nick Hern Books, 2008.