Schaefer, R. T. (1988). Racial and ethnic groups (3ª ed.). Scott, Foresman.
Chicago Style aipamenaSchaefer, Richard T. Racial and Ethnic Groups. 3ª ed. Scott, Foresman, 1988.
MLA aipamenaSchaefer, Richard T. Racial and Ethnic Groups. 3ª ed. Scott, Foresman, 1988.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.