Cita APA (7th ed.)

Willoughby, D. (2007). The world of music (6th ed.). McGraw-Hill.

Cita Chicago (17th ed.)

Willoughby, David. The World of Music. 6th ed. Boston: McGraw-Hill, 2007.

Cita MLA (9th ed.)

Willoughby, David. The World of Music. 6th ed. McGraw-Hill, 2007.