APA

Spaeth S., . (1940). Barber shop ballads. New York: Prentice-Hall, Inc.

Chicago

Spaeth Sigmund, . 1940. Barber shop ballads. New York: Prentice-Hall, Inc.

Harvard

Spaeth S., . (1940). Barber shop ballads. New York: Prentice-Hall, Inc.

MLA

Spaeth Sigmund, . Barber shop ballads. New York: Prentice-Hall, Inc. 1940.