APA (7th ed.) Citation

Active Communications (Firm), Crumb, G., & Knott, T. J. (2007). George Crumb: Apparition. Active Communications.

Chicago Style (17th ed.) Citation

Active Communications (Firm), George Crumb, and Thomas J. Knott. George Crumb: Apparition. [Stow, Mass.]: Active Communications, 2007.

MLA (9th ed.) Citation

Active Communications (Firm), et al. George Crumb: Apparition. Active Communications, 2007.