Cita APA (7th ed.)

Schaefer, R. T. (1990). Racial and ethnic groups (4th ed.). Harper Collins.

Cita Chicago (17th ed.)

Schaefer, Richard T. Racial and Ethnic Groups. 4th ed. USA: Harper Collins, 1990.

Cita MLA (9th ed.)

Schaefer, Richard T. Racial and Ethnic Groups. 4th ed. Harper Collins, 1990.